CVE-2013-4207

medium

Published 2013-08-19 · Modified 2026-04-29

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CVSS v3

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CVSS v4 NEW

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not yet in upstream

VIR risk

4.3

Description

Buffer overflow in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) via an invalid DSA signature that is not properly handled during computation of a modular inverse and triggers the overflow during a division by zero by the bignum functionality, a different vulnerability than CVE-2013-4206.

Predictions

Exploit likelihood

20%

Patch ETA

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Heuristic predictions, AS-IS, for prioritization only.

Mitigations

No mitigations published for this CVE yet.

The vendor-content worker queues fetches as references arrive (check back in a few minutes). Or — if you've already worked around this in production — publish your fix to the community-verified tier.

✚ Propose a mitigation on Community → Mitigations published via the community go through AI scoring + 2 human reviewers + 7-day silent objection window before landing here with source_tier=community-verified.

OS impact

OS	Version	Status	Fixed in
debian	bookworm	fixed	`3.7.3-1`
debian	bullseye	fixed	`3.7.3-1`
debian	forky	fixed	`3.7.3-1`
debian	sid	fixed	`3.7.3-1`
debian	trixie	fixed	`3.7.3-1`

Application impact

Vendor	Product	Versions
putty	putty	`0.45`
putty	putty	`0.46`
putty	putty	`0.47`
putty	putty	`0.48`
putty	putty	`0.49`
putty	putty	`0.50`
putty	putty	`0.51`
putty	putty	`0.52`
putty	putty	`0.53b`
putty	putty	`0.54`
putty	putty	`0.55`
putty	putty	`0.56`
putty	putty	`0.57`
putty	putty	`0.58`
putty	putty	`0.59`
putty	putty	`0.60`
putty	putty	`0.61`
putty	putty	`2010-06-01`
simon_tatham	putty	`{"endIncluding":"0.62"}`
simon_tatham	putty	`0.53`

References

CWEs

CWE-119

Community-verified mitigations for this CVE will appear above when contributors publish them.

Verify integrity in audit chain (admin only). AS-IS.