Bug 2228743 (CVE-2023-29409) - CVE-2023-29409 golang: crypto/tls: slow verification of certificate chains containing large RSA keys
Summary: CVE-2023-29409 golang: crypto/tls: slow verification of certificate chains co...
Keywords:
Status: NEW
Alias: CVE-2023-29409
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Nobody
QA Contact:
URL:
Whiteboard:
Depends On: 2228829 2228830 2228831 2228832 2228833 2228836 2228837 2228838 2228839 2228840 2228842 2228843 2228844 2229061 2229062 2229063 2229064 2229065 2229066 2229067 2229068 2229069 2229070 2229072 2229073 2229074 2229075 2229076 2229078 2229079 2229081 2229082 2229083 2229084 2229085 2229086 2229087 2229089 2229090 2229091 2229092 2229093 2229094 2229620 2229621 2228834 2228835 2229071 2229077 2229080 2229088 2230278
Blocks: 2228694
TreeView+ depends on / blocked
 
Reported: 2023-08-03 07:10 UTC by Avinash Hanwate
Modified: 2023-08-09 16:05 UTC (History)
149 users (show)

Fixed In Version: Go 1.20.7, Go 1.19.12
Doc Type: If docs needed, set a value
Doc Text:
A denial of service vulnerability was found in the Golang Go package caused by an uncontrolled resource consumption flaw. By persuading a victim to use a specially crafted certificate with large RSA keys, a remote attacker can cause a client/server to expend significant CPU time verifying signatures, resulting in a denial of service condition.
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Description Avinash Hanwate 2023-08-03 07:10:56 UTC
Extremely large RSA keys in certificate chains can cause a client/server to expend significant CPU time verifying signatures. With fix, the size of RSA keys transmitted during handshakes is restricted to <= 8192 bits. Based on a survey of publicly trusted RSA keys, there are currently only three certificates in circulation with keys larger than this, and all three appear to be test certificates that are not actively deployed. It is possible there are larger keys in use in private PKIs, but we target the web PKI, so causing breakage here in the interests of increasing the default safety of users of crypto/tls seems reasonable.

https://go.dev/cl/515257
https://groups.google.com/g/golang-announce/c/X0b6CsSAaYI/m/Efv5DbZ9AwAJ
https://pkg.go.dev/vuln/GO-2023-1987
https://go.dev/issue/61460

Comment 6 Avinash Hanwate 2023-08-07 06:07:00 UTC
Created golang tracking bugs for this issue:

Affects: epel-all [bug 2229620]
Affects: fedora-all [bug 2229621]

Comment 7 Debarshi Ray 2023-08-07 17:42:48 UTC
Were the bugs for this CVE created correctly?

I got bugs RHEL 8 bugs for toolbox for both the rolling (bug 2229077) and 4.0 (bug 2229071) module streams, but none for RHEL 9.  In comparison, I found RHEL 9 bugs for podman (bug 2229091) and golang (bug 2229065).

So, it seems like RHEL 9 is affected, but then why is there no RHEL 9 toolbox bug?  There's no difference in toolbox across RHEL 8 and 9 that could be relevant to this CVE.

I have seen this happen a few times recently:
https://bugzilla.redhat.com/show_bug.cgi?id=2196026#c33
https://bugzilla.redhat.com/show_bug.cgi?id=2196027#c45

... and it makes me wonder if there's something wrong with the process that's used to file these bugs.

Comment 9 Avinash Hanwate 2023-08-09 09:03:50 UTC
In reply to comment #7:
> Were the bugs for this CVE created correctly?
> 
> I got bugs RHEL 8 bugs for toolbox for both the rolling (bug 2229077) and
> 4.0 (bug 2229071) module streams, but none for RHEL 9.  In comparison, I
> found RHEL 9 bugs for podman (bug 2229091) and golang (bug 2229065).
> 
> So, it seems like RHEL 9 is affected, but then why is there no RHEL 9
> toolbox bug?  There's no difference in toolbox across RHEL 8 and 9 that
> could be relevant to this CVE.
> 
> I have seen this happen a few times recently:
> https://bugzilla.redhat.com/show_bug.cgi?id=2196026#c33
> https://bugzilla.redhat.com/show_bug.cgi?id=2196027#c45
> 
> ... and it makes me wonder if there's something wrong with the process
> that's used to file these bugs.
Hi @debarshi, we are working on fixing this issue. I have filed a tracker for rhel-9/toolbox.

Comment 10 Debarshi Ray 2023-08-09 16:05:41 UTC
(In reply to Avinash Hanwate from comment #9)
> ... we are working on fixing this issue. I have filed a tracker
> for rhel-9/toolbox.

That's fantastic, thanks!


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