CVE-2013-4206: putty
Vulnerability summary
CVE-2013-4206 is a medium (CVSS 6.8) vulnerability in putty. EPSS estimates a 2.48% chance of exploitation in the next 30 days, higher than 84.5% of scored vulnerabilities.
Not severe (CVSS 6.8, network access); no exploitation reported by the 5 checked sources
Source freshness unavailable
How is this decided?Advisory lineage
Upstream 0 · Downstream 3 · Related 1Timeline
- 19-08-2013PublishedVulnerability first disclosed.
- 06-08-2024Last modifiedVulnerability information updated.
Description
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.
CVSS metrics
1 score · 1 source · 1 versionEPSS trend
Probability
2.48%
Chance of exploitation in the next 30 days
Percentile
85%
Versus all other CVEs
30-day change
No change 0.00 pp
From 2.48% on 04-10-2026
Known exploited
Compare KEV catalogs
CISA KEVNot in the CISA KEV catalog.
ENISA CNWNot in the ENISA CNW catalog.
CIRCLNot in the CIRCL catalog.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Known conditions: network-reachable, no authentication (CVSS vector). Other conditions: not stated in public data.
Debian2 products
- filezilla< 3.7.3-1
- putty< 0.63-1
Putty1 product
- putty0.45 | 0.46 | 0.47 | 0.48 | 0.49 | 0.50 | 0.51 | 0.52 | 0.53b | 0.54 | 0.55 | 0.56 | 0.57 | 0.58 | 0.59 | 0.60 | 0.61 | 2010-06-01:r8967
Simon_tatham1 product
- putty≤ 0.62 | 0.53
3 vendors · 4 products
References
8 links- www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modmul.htmlX Refsource CONFIRMVendor Advisory
