CVE-2013-4206
MEDIUM · CVSS 6.8EPSS 2.5%EU EUVD
Heap-based buffer underflow in the modmul function in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of service (crash) and possibly trigger memory corruption or code execution via a crafted DSA signature, which is not properly handled when performing certain bit-shifting operations during modular multiplication.
Key facts
- CVSS score
- 6.8 (v2.0)
- Severity
- MEDIUM
- CVSS vector
AV:N/AC:M/Au:N/C:P/I:P/A:P- Weakness (CWE)
- CWE-119
- EPSS score
- 2.5% (85th percentile)
- In CISA KEV
- No
- In EU EUVD
- Yes (EUVD-2013-4111)
- Published
- August 19, 2013
- NVD last modified
- June 16, 2026
- Status
- Modified
EU Vulnerability Database (EUVD)
This vulnerability is also tracked by ENISA as EUVD-2013-4111 in the EU Vulnerability Database. Last updated in EUVD on August 6, 2024.
View on the EU Vulnerability DatabaseAffected products
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- putty / putty
- simon tatham / putty
- simon tatham / putty
References
- http://lists.opensuse.org/opensuse-updates/2013-08/msg00035.html
- http://secunia.com/advisories/54379(Vendor Advisory)
- http://secunia.com/advisories/54533
- http://svn.tartarus.org/sgt/putty/sshbn.c?sortby=date&r1=9977&r2=9976&pathrev=9977(Patch)
- http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modmul.html(Vendor Advisory)
- http://www.debian.org/security/2013/dsa-2736
- http://www.openwall.com/lists/oss-security/2013/08/06/11
Last updated September 17, 2026 · Source: NVD, CISA KEV, FIRST.org EPSS
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