Serious Discussion Behavior vs Signature: which is the best strategy?

[RoboMan]

I’ve been testing different free AV products in a light real-world scenario on Windows 11 (typical home user behavior).

What I noticed is that most engines score high in signature-based tests, but when exposed to newly packed samples or slightly modified droppers, detection often shifts from static pre-execution blocking to behavioral containment. Pretty common statement.

In some cases, execution is allowed briefly before behavioral modules step in.

That made me question something about detection logic versus marketing claims.

From a practical protection standpoint, is it technically better for an AV to:

• block more aggressively at pre-execution with higher false positives

or

• allow uncertain files to execute under behavioral monitoring and intervene only if malicious patterns emerge?

In 2026 threat landscape terms, which architecture is logically more resilient? And which strategy are you personally more inclined to accept from the product you use?

PS: free BoraMurdar

 

[Khushal]

I’ve been testing different free AV products in a light real-world scenario on Windows 11 (typical home user behavior).

What I noticed is that most engines score high in signature-based tests, but when exposed to newly packed samples or slightly modified droppers, detection often shifts from static pre-execution blocking to behavioral containment. Pretty common statement.

In some cases, execution is allowed briefly before behavioral modules step in.

That made me question something about detection logic versus marketing claims.

From a practical protection standpoint, is it technically better for an AV to:

• block more aggressively at pre-execution with higher false positives

or

• allow uncertain files to execute under behavioral monitoring and intervene only if malicious patterns emerge?

In 2026 threat landscape terms, which architecture is logically more resilient? And which strategy are you personally more inclined to accept from the product you use?

PS: free BoraMurdar

I prefer a weaker static analysis with fewer false positives, paired up with smart behaviour blocker

 

[Halp2001]

I prefer that the known threats get blocked right away, and the uncertain ones are watched closely.Signatures for the obvious, behavior for the creative side of malware.

 

[lokamoka820]

I prefer ease of use over maximum protection, and although MS Defender is sufficient for me, I always consider replacing it when it starts giving me false positives.

 

[RansomwareRemediation]

The signatures will always be worse than the behavior blocker, but the signatures block the pre-execution, which is good, the issue is when the signature does not exist for said malware. That's why antiviruses like Eset, which are completely dependent on signatures, don't convince me.

 

[SeriousHoax]

Signatures are better if the quality of the signature is good like ESET because you can detect things early.
Like in this test, ESET is the only one that blocked all threats pre-execution by their signatures & heuristics while others required behavior blocker/detection on execution for a few of the samples.

https://www.mrg-effitas.com/wp-content/uploads/2025/08/MRG_Effitas_360_Q2_2025_v1_1.pdf

Or in this Advanced Threat Protection test of AVC where Bitdefender detected 13/15 pre-execution, 2 of them on execution needing 0 post-execution based detection.

Advanced Threat Protection Test 2025 - Enterprise

Check out AV-Comparatives' newly released Advanced Threat Protection Test 2025 for Enterprise security products

www.av-comparatives.org

AVC analogy is perfect, "A good burglar alarm should go off as soon as someone breaks into your home. It should not wait until they start stealing."

So I prefer more pre-execution detection but with very few false positives.
Having great signatures + great behavior blocker + close to zero false positives + lite in performance impact would be the most ideal combination if possible. Sometimes false positives either by signatures or behavior blocker can be more annoying than being infected. So no matter the approach, false positives should always be very very low along with high detection rates.

 

[Parkinsond]

The role of behavioral detection is limited to catching missed samples post-execution when signatures fail to detect at the pre-execution stage.
Personally, I find pro-pre-execution prevention is the safest strategy.

 

[lokamoka820]

Having great signatures + great behavior blocker + close to zero false positives + lite in performance impact would be the most ideal combination if possible.

In a word: Kaspersky.

 

[RoboMan]

In a word: Kaspersky.

Plus an zero trust module which is Application Control

 

[SeriousHoax]

In a word: Kaspersky.

Yeah, Kaspersky is very close to this.
But for the sake of argument, one could say, its pre-execution detections are not as high as Avast, Avira, BD, ESET. Even though it's light, its CPU usage on average is higher than some products. I saw someone once saying that his laptop battery lasts longer with Bitdefender compared to Kaspersky.

 

[RansomwareRemediation]

Signatures are better if the quality of the signature is good like ESET because you can detect things early.
Like in this test, ESET is the only one that blocked all threats pre-execution by their signatures & heuristics while others required behavior blocker/detection on execution for a few of the samples.

https://www.mrg-effitas.com/wp-content/uploads/2025/08/MRG_Effitas_360_Q2_2025_v1_1.pdf

Or in this Advanced Threat Protection test of AVC where Bitdefender detected 13/15 pre-execution, 2 of them on execution needing 0 post-execution based detection.

Advanced Threat Protection Test 2025 - Enterprise

Check out AV-Comparatives' newly released Advanced Threat Protection Test 2025 for Enterprise security products

www.av-comparatives.org

AVC analogy is perfect, "A good burglar alarm should go off as soon as someone breaks into your home. It should not wait until they start stealing."

So I prefer more pre-execution detection but with very few false positives.
Having great signatures + great behavior blocker + close to zero false positives + lite in performance impact would be the most ideal combination if possible. Sometimes false positives either by signatures or behavior blocker can be more annoying than being infected. So no matter the approach, false positives should always be very very low along with high detection rates.

The Leo test where all the data on the Eset machine is encrypted, because its supposed signatures are not capable of reacting. On the other hand, an antivirus that has a balance between signatures and BB comes out victorious, as is the case with Kaspersky and Bitdefender. Signatures are irrelevant when they don't work, what matters is that the av protects you. And even if the antivirus releases a signature, the damage has already been done.

 

[Minimalist]

I prefer to use antivirus which is less aggresive and produces less false positives. For me it's much more likely to be hit by false positive than by malware.
Since, from past experience, I encounter malware approx. once every ten years, it also doesn't matter that much to me if AM achieves 90, 95 or 99% detection rate in some malware detection test. For me it's much more important to use AM that is not prone to FPs and doesn't impact system performance.

 

[Parkinsond]

The Leo test where all the data on the Eset machine is encrypted, because its supposed signatures are not capable of reacting. On the other hand, an antivirus that has a balance between signatures and BB comes out victorious, as is the case with Kaspersky and Bitdefender. Signatures are irrelevant when they don't work, what matters is that the av protects you. And even if the antivirus releases a signature, the damage has already been done.

The applies if the behavioral detection was delayed just one second.

 

[Miravi]

Most users will feel alienated by a high false positive ratio, and they shouldn't expect that from a top-tier consumer antivirus.

Nowadays, the top products employ some very sophisticated techniques to try to get the best of both worlds: uncovering polymorphic/zero-day malware variants without annoying you. File reputation and cloud insights quickly reveal a profile of the subject, and from there machine learning has done wonders for generic/behavioral heuristic analysis.

ESET is known for using a signature-centric approach, for example, but in their case they've demonstrated that supervised machine learning can really push the envelope of what's possible for heuristic signatures.

The behavior blocker that follows static analysis in a mainstream product will need a delicate touch, too. Successfully implementing security software that works for everyone is an art.

 

[RansomwareRemediation]

Most users will feel alienated by a high false positive ratio, and they shouldn't expect that from a top-tier consumer antivirus.

Nowadays, the top products employ some very sophisticated techniques to try to get the best of both worlds: uncovering polymorphic/zero-day malware variants without annoying you. File reputation and cloud insights quickly reveal a profile of the subject, and from there machine learning has done wonders for generic/behavioral heuristic analysis.

ESET is known for using a signature-centric approach, for example, but in their case they've demonstrated that supervised machine learning can really push the envelope of what's possible for heuristic signatures.

The behavior blocker that follows static analysis in a mainstream product will need a delicate touch, too. Successfully implementing security software that works for everyone is an art.

Today antiviruses have a very low rate of false positives.
I have seen many tests where Eset fails terribly due to not having a competent BB. That is why there has to be a balance between BB and signatures, something that does not happen in Eset. That's why antiviruses like Kaspersky, Bitdefender or even Norton tend to react better in different scenarios. Obviously everything fails.

 

[Miravi]

Today antiviruses have a very low rate of false positives.
I have seen many tests where Eset fails terribly due to not having a competent BB. That is why there has to be a balance between BB and signatures, something that does not happen in Eset. That's why antiviruses like Kaspersky, Bitdefender or even Norton tend to react better in different scenarios. Obviously everything fails.

It's true. I haven't seen much of any evidence that ESET monitors behavior. I think they would do well to make upgrades in this department and move beyond the old-fashioned HIPS. Nevertheless, their product served as a good example because it's still been able to excel in a number of tests, which was already brought up earlier in the thread.

Every modern antivirus employs similar pre-execution/static heuristic analysis to ESET. Avast calls their equivalent technology MDE (Malware Detection Engine).

 

[Khushal]

The applies if the behavioral detection was delayed just one second.

that was a ransomware test not a mbr writer test wherein each second is important. ESET ignored the ransomware and was not late. With ransomware u can never be late during its process as even if u are u will save some files.

 

[Khushal]

It's true. I haven't seen much of any evidence that ESET monitors behavior. I think they would do well to make upgrades in this department and move beyond the old-fashioned HIPS. Nevertheless, their product served as a good example because it's still been able to excel in a number of tests, which was already brought up earlier in the thread.

Every modern antivirus employs similar pre-execution/static heuristic analysis to ESET. Avast calls their equivalent technology MDE (Malware Detection Engine).

The lack of Behavior blocking in ESET is a trade-off for less CPU utilization and faster system. Although recent AV tests suggests that K has bettered ESET in that regard.

 

[Antimalware18]

I prefer agressive pre execution detection but backed up with a powerful behavioral engine.

 

[Parkinsond]

that was a ransomware test not a mbr writer test wherein each second is important

You mean the behavioral protection can delay as much as it want in blocking ransomware not detected by signature, and the files will be intact, unencrypted?