Re: Why are recent Firefox (for Windows) downloads ALL being found to contain ransomware?

"Valerie Snyder \(valsnyde\) via clamav-users" <[email protected]> Mon, 30 Mar 2026 22:03:23 +0000
Newsgroups gmane.comp.security.virus.clamav.user
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When you have "AlertExceedsMax yes" in your config, then exceeding scan lim=
its are treated as alerts / infected regardless of if it finds any signatur=
e matches.

Respectfully,
Val

Valerie Snyder (she/they)
ClamAV Development
Talos
Cisco Systems, Inc.
________________________________
From: clamav-users <[email protected]> on behalf of Pau=
l Kosinski via clamav-users <[email protected]>
Sent: Saturday, March 28, 2026 10:43 AM
To: Andrew C Aitchison <[email protected]>
Cc: Paul Kosinski <[email protected]>; [email protected] <=
[email protected]>
Subject: Re: [clamav-users] Why are recent Firefox (for Windows) downloads =
ALL being found to contain ransomware?

On Fri, 27 Mar 2026 12:23:35 +0000 (GMT)
Andrew Aitchison via clamav-users <[email protected]> wrote:

> I note that the scan takes around two minutes
> which may be enough for a timeout such as ReadTimeout to kick in.

------------------------------------
------------------------------------

If I reduce the max scan time limit for clamd to 30 secs, I get the followi=
ng:

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Firefox Setup 115.34.0esr.exe: Heuristics.Limits.Exceeded.MaxScanTime FOUND

----------- SCAN SUMMARY -----------
Infected files: 1
Time: 30.619 sec (0 m 30 s)
Start Date: 2026:03:27 22:29:05
End Date:   2026:03:27 22:29:36
RC =3D 1
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

which is quite different from:

=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
Firefox Setup 115.34.0esr.exe: Win.Trojan.Spora-7724442-0 FOUND

----------- SCAN SUMMARY -----------
Infected files: 1
Time: 87.618 sec (1 m 27 s)
Start Date: 2026:03:27 22:41:03
End Date:   2026:03:27 22:42:31
RC =3D 1
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D

P.S. In both cases I have used the verbose reporting option. It's interesti=
ng that the first case also shows 1 infected file -- perhaps it found the T=
rojan before it timed out?
_______________________________________________

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<html>
<head>
<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dus-ascii"=
>
<style type=3D"text/css" style=3D"display:none;"> P {margin-top:0;margin-bo=
ttom:0;} </style>
</head>
<body dir=3D"ltr">
<div class=3D"elementToProof" style=3D"font-family: Aptos, Aptos_EmbeddedFo=
nt, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; c=
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olor_rgb_0__0__0_, var(--darkreader-text-000000, #e8e6e3));" data-darkreade=
r-inline-color=3D"">
When you have &quot;AlertExceedsMax yes&quot; in your config, then exceedin=
g scan limits are treated as alerts / infected regardless of if it finds an=
y signature matches.&nbsp;</div>
<div id=3D"Signature" class=3D"elementToProof">
<div class=3D"elementToProof" style=3D"font-family: Aptos, Aptos_EmbeddedFo=
nt, Aptos_MSFontService, Calibri, Helvetica, sans-serif; font-size: 12pt; c=
olor: rgb(0, 0, 0); --darkreader-inline-color: var(--darkreader-text--darkC=
olor_rgb_0__0__0_, var(--darkreader-text-000000, #e8e6e3));" data-darkreade=
r-inline-color=3D"">
<br>
</div>
<div class=3D"elementToProof" style=3D"font-family: Calibri, Arial, Helveti=
ca, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); --darkreader-inline-c=
olor: var(--darkreader-text--darkColor_rgb_0__0__0_, var(--darkreader-text-=
000000, #e8e6e3));" data-darkreader-inline-color=3D"">
Respectfully,</div>
<div class=3D"elementToProof" style=3D"font-family: Calibri, Arial, Helveti=
ca, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); --darkreader-inline-c=
olor: var(--darkreader-text--darkColor_rgb_0__0__0_, var(--darkreader-text-=
000000, #e8e6e3));" data-darkreader-inline-color=3D"">
Val</div>
<div class=3D"elementToProof" style=3D"font-family: Calibri, Arial, Helveti=
ca, sans-serif; font-size: 12pt; color: rgb(0, 0, 0); --darkreader-inline-c=
olor: var(--darkreader-text--darkColor_rgb_0__0__0_, var(--darkreader-text-=
000000, #e8e6e3));" data-darkreader-inline-color=3D"">
<br>
<span style=3D"font-family: Helvetica; font-size: 12px;">Valerie Snyder (sh=
e/they)</span><br>
<span style=3D"font-family: Helvetica; font-size: 12px;">ClamAV Development=
</span><br>
<span style=3D"font-family: Helvetica; font-size: 12px;">Talos</span><br>
<span style=3D"font-family: Helvetica; font-size: 12px;">Cisco Systems, Inc=
.</span><br>
</div>
</div>
<div id=3D"appendonsend"></div>
<hr style=3D"display:inline-block;width:98%" tabindex=3D"-1">
<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=
yle=3D"font-size:11pt" color=3D"#000000"><b>From:</b> clamav-users &lt;clam=
[email protected]&gt; on behalf of Paul Kosinski via clamav=
-users &lt;[email protected]&gt;<br>
<b>Sent:</b> Saturday, March 28, 2026 10:43 AM<br>
<b>To:</b> Andrew C Aitchison &lt;[email protected]&gt;<br>
<b>Cc:</b> Paul Kosinski &lt;[email protected]&gt;; clamav-users@lists=
.clamav.net &lt;[email protected]&gt;<br>
<b>Subject:</b> Re: [clamav-users] Why are recent Firefox (for Windows) dow=
nloads ALL being found to contain ransomware?</font>
<div>&nbsp;</div>
</div>
<div class=3D"BodyFragment"><font size=3D"2"><span style=3D"font-size:11pt;=
">
<div class=3D"PlainText">On Fri, 27 Mar 2026 12:23:35 +0000 (GMT)<br>
Andrew Aitchison via clamav-users &lt;[email protected]&gt; wro=
te:<br>
<br>
&gt; I note that the scan takes around two minutes<br>
&gt; which may be enough for a timeout such as ReadTimeout to kick in.<br>
<br>
------------------------------------<br>
------------------------------------<br>
<br>
If I reduce the max scan time limit for clamd to 30 secs, I get the followi=
ng:<br>
<br>
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>
Firefox Setup 115.34.0esr.exe: Heuristics.Limits.Exceeded.MaxScanTime FOUND=
<br>
<br>
----------- SCAN SUMMARY -----------<br>
Infected files: 1<br>
Time: 30.619 sec (0 m 30 s)<br>
Start Date: 2026:03:27 22:29:05<br>
End Date:&nbsp;&nbsp; 2026:03:27 22:29:36<br>
RC =3D 1<br>
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>
<br>
which is quite different from:<br>
<br>
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>
Firefox Setup 115.34.0esr.exe: Win.Trojan.Spora-7724442-0 FOUND<br>
<br>
----------- SCAN SUMMARY -----------<br>
Infected files: 1<br>
Time: 87.618 sec (1 m 27 s)<br>
Start Date: 2026:03:27 22:41:03<br>
End Date:&nbsp;&nbsp; 2026:03:27 22:42:31<br>
RC =3D 1<br>
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D<br>
<br>
P.S. In both cases I have used the verbose reporting option. It's interesti=
ng that the first case also shows 1 infected file -- perhaps it found the T=
rojan before it timed out?<br>
_______________________________________________<br>
<br>
Manage your clamav-users mailing list subscription / unsubscribe:<br>
<a href=3D"https://lists.clamav.net/mailman/listinfo/clamav-users">https://=
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<br>
<br>
Help us build a comprehensive ClamAV guide:<br>
<a href=3D"https://github.com/Cisco-Talos/clamav-documentation">https://git=
hub.com/Cisco-Talos/clamav-documentation</a><br>
<br>
<a href=3D"https://docs.clamav.net/#mailing-lists-and-chat">https://docs.cl=
amav.net/#mailing-lists-and-chat</a><br>
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_______________________________________________

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