CVE-2013-4207
Buffer overflow in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of...
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.
Exploit likelihood
What each source reports
NVD Score used
4.3
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.
- Record
CVE-2013-4207- CVSS 2.0
- 4.3 Medium
AV:N/AC:M/Au:N/C:N/I:N/A:P - Weakness
- CWE-119
- Updated
- 2026-11-02
CVE List No score
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.
- Record
CVE-2013-4207- Updated
- 2026-11-02
EUVDEUVD-2013-4112 No score
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.
- Record
EUVD-2013-4112- Updated
- 2026-11-03
GitHub AdvisoriesGHSA-gqcg-rpgj-92fp No score
Buffer overflow in sshbn.c in PuTTY before 0.63 allows remote SSH servers to cause a denial of...
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.
- Record
GHSA-gqcg-rpgj-92fp- Weakness
- CWE-119
- Updated
- 2026-11-02
OSV No score
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.
- Record
CVE-2013-4207- Updated
- 2026-11-02
OSVDEBIAN-CVE-2013-4207 No score
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.
- Record
DEBIAN-CVE-2013-4207- Updated
- 2026-11-02
OSVMGASA-2013-0242 No score
Updated putty and filezilla packages fixes security vulnerability
PuTTY versions 0.62 and earlier - as well as all software that integrates these versions of PuTTY - are vulnerable to an integer overflow leading to heap overflow during the SSH handshake before authentication, caused by improper bounds checking of the length parameter received from the SSH server. This allows remote attackers to cause denial of service, and may have more severe impact on the operation of software that uses PuTTY code (CVE-2013-4852).
PuTTY versions 0.62 and earlier - as well as all software that integrates these versions of PuTTY - are vulnerable to a heap-corrupting buffer underrun bug in the modmul function which performs modular multiplication (CVE-2013-4206).
PuTTY versions 0.62 and earlier - as well as all software that integrates these versions of PuTTY - are vulnerable to a buffer overflow vulnerability in the calculation of modular inverses when verifying a DSA signature (CVE-2013-4207).
PuTTY versions 0.62 and earlier - as well as all software that integrates these versions of PuTTY - are vulnerable to private keys left in memory after being used by PuTTY tools (CVE-2013-4208).
- Record
MGASA-2013-0242- Updated
- 2026-11-02
OSVopenSUSE-SU-2024:10399-1 No score
filezilla-3.23.0.2-1.1 on GA media
These are all security issues fixed in the filezilla-3.23.0.2-1.1 package on the GA media of openSUSE Tumbleweed.
- Record
openSUSE-SU-2024:10399-1- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
filezillaDebian:12 |
before 3.7.3-1 | 3.7.3-1 |
filezillaDebian:13 |
before 3.7.3-1 | 3.7.3-1 |
filezillaDebian:14 |
before 3.7.3-1 | 3.7.3-1 |
puttyDebian:12 |
before 0.63-1 | 0.63-1 |
puttyDebian:13 |
before 0.63-1 | 0.63-1 |
puttyDebian:14 |
before 0.63-1 | 0.63-1 |
puttyDebian:6.0 |
before 0.60+2010-02-20-1+squeeze2, plus listed versions 0.60+2010-02-20-10.60+2010-02-20-1+squeeze1 |
0.60+2010-02-20-1+squeeze2 |
puttyDebian:7 |
before 0.62-9+deb7u1, plus listed versions 0.62-9 |
0.62-9+deb7u1 |
puttyMageia:2 |
before 0.63-1.mga2 | 0.63-1.mga2 |
filezillaMageia:2 |
before 3.7.3-1.mga2 | 3.7.3-1.mga2 |
puttyMageia:3 |
before 0.63-1.mga3 | 0.63-1.mga3 |
filezillaMageia:3 |
before 3.7.3-1.mga3 | 3.7.3-1.mga3 |
filezillaopenSUSE:Tumbleweed |
before 3.23.0.2-1.1 | 3.23.0.2-1.1 |
History
| Recorded | Changed | Sources |
|---|---|---|
| aliases | EUVD | |
| first indexed | CVE List, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2013-4207 is a medium vulnerability (CVSS 4.3) in Putty, published August 9, 2013. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 1.83%, the 78th percentile. Fixed in filezilla 3.7.3-1.
References
openwall.com/lists/oss-security/2013/08/06/11
secunia.com/advisories/54533
debian.org/security/2013/dsa-2736
lists.opensuse.org/opensuse-updates/2013-08/msg00035.html
chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-bignum-division-by-zero.html
secunia.com/advisories/54379
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nvd.nist.gov/vuln/detail/CVE-2013-4207
github.com/advisories/GHSA-gqcg-rpgj-92fp
security-tracker.debian.org/tracker/CVE-2013-4207
advisories.mageia.org/MGASA-2013-0242.html
bugs.mageia.org/show_bug.cgi?id=10925
chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-modmul.html
chiark.greenend.org.uk/~sgtatham/putty/wishlist/private-key-not-wiped.html
openwall.com/lists/oss-security/2013/08/06/13
search-lab.hu/advisories/secadv-20130722
suse.com/security/cve/CVE-2013-4206
suse.com/security/cve/CVE-2013-4207
suse.com/security/cve/CVE-2013-4208
suse.com/security/cve/CVE-2013-4852