Integer overflow in Asterisk Certified
CVE-2021-37706
PJSIP is a free and open source multimedia communication library written in C language implementing standard based protocols such as SIP, SDP, RTP, STUN, TURN, and ICE. In affected versions if the incoming STUN message contains an ERROR-CODE attribute, the header length is not checked before performing a subtraction operation, potentially resulting in an integer underflow scenario. This issue affects all users that use STUN. A malicious actor located within the victim’s network may forge and send a specially crafted UDP (STUN) message that could remotely execute arbitrary code on the victim’s machine. Users are advised to upgrade as soon as possible. There are no known workarounds.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 7.3 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L.
EPSS exploit prediction
EPSS: 0.046 (91.3th percentile), scored .
Low probability of exploitation in the next 30 days, but still tracked. 91st percentile — 91.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.046 · newest: 0.046 · change: 0.000
Affected products
- Asterisk Certified — versions 16.8.0
- Pjsip Pjproject — versions <= 2.11.1
- Sangoma Asterisk
- Teluu Pjsip
- Debian Linux — versions 9.0, 10.0
Weakness classification (CWE)
Public proof-of-concept exploits
References
- github.com/pjsip/pjproject/security/advisories/GHSA-2qpg-f6wf-w984 (Patch, Third Party Advisory)
- github.com/pjsip/pjproject/commit/15663e3f37091069b8c98a7fce680dc04bc8e865 (Patch, Third Party Advisory)
- seclists.org/fulldisclosure/2022/Mar/0 (mailing-list, Patch, Mailing List, Third Party Advisory)
- packetstormsecurity.com/files/166225/Asterisk-Project-Security-Advisory-AST-202… (VDB Entry, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2022/03/msg00035.html (mailing-list, Mailing List, Third Party Advisory)
- security.gentoo.org/glsa/202210-37 (vendor-advisory, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2022/11/msg00021.html (mailing-list, Mailing List, Third Party Advisory)
- www.debian.org/security/2022/dsa-5285 (vendor-advisory, Third Party Advisory)
- lists.debian.org/debian-lts-announce/2023/08/msg00038.html (mailing-list)
- af854a3a-2127-422b-91ae-364da2661108
Frequently asked questions
- What is CVE-2021-37706?
- CVE-2021-37706 is a high-severity vulnerability in Asterisk Certified, classified under Integer Underflow. CVSS score: 7.3/10. Published 2021-12-22.
- How severe is CVE-2021-37706?
- High severity. CVSS v3 base score is 7.3 out of 10.
- Is CVE-2021-37706 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.