CVE-2021-37706

highpriority · track · 41EPSS 0.049 · 92 %ileDEEURUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

4.92% (92nd) EPSS

CVSS 9.3 · high

Is it mine?

21 products

Check your exposure

Who says so?

5 sources

cnnvd · enisa_euvd · fstec_bdu · cert_bund

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

9.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · high–critical · 7.3–9.8

v2.09.3highAV:N/AC:M/Au:N/C:C/I:C/A:Cprimary · NVD / NIST USexploitability 8.6 · impact 10

v3.19.8criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 5.9

v3.17.3highAV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · FSTEC (BDU) RU

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · ENISA EU

v3.17.3highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:Lsecondary · security-advisories@github.comexploitability 3.9 · impact 3.4

v3.19criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-191USprimaryCWE-191US

affected products (21)

Products and version ranges known to be affected.

Debian Linuxall versionscert_bundDEcpe:/o:debian:debian_linux:-
Digium Certified Asterisk <16.8-cert13all versionscert_bundDE
Open Source Asterisk <16.24.1all versionscert_bundDE
Open Source Asterisk <18.10.1all versionscert_bundDE
Open Source Asterisk <19.2.1all versionscert_bundDE
Ubuntu Linuxall versionscert_bundDEcpe:/o:canonical:ubuntu_linux:-
Digium Certified Asterisk< 16.8-cert13cert_bundDE
Open Source Asterisk< 16.24.1cert_bundDE
Open Source Asterisk< 18.10.1cert_bundDE
Open Source Asterisk< 19.2.1cert_bundDE
pjsip pjproject≤ ≤ 2.11.1enisa_euvdEU
АО «НППКТ» ОСОН ОСнова Оnyx≤ 2.10fstec_bduRU
Сообщество свободного программного обеспечения PJSIP≤ 2.11.1fstec_bduRU
asterisk certified asterisk< 16.8.0nvdUScpe:2.3:a:asterisk:certified_asterisk:*:*:*:*:*:*:*:*
asterisk certified asterisk= 16.8.0nvdUScpe:2.3:a:asterisk:certified_asterisk:*:*:*:*:*:*:*:*
debian debian linux= 10.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
debian debian linux= 9.0nvdUScpe:2.3:o:debian:debian_linux:*:*:*:*:*:*:*:*
sangoma asterisk16.0.0 → 16.24.1nvdUScpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*
sangoma asterisk18.0.0 → 18.10.1nvdUScpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*
sangoma asterisk19.0.0 → 19.2.1nvdUScpe:2.3:a:sangoma:asterisk:*:*:*:*:*:*:*:*

showing 20 of 21

advisories (1)

Vendor and ecosystem advisories describing this.

WID-SEC-W-2022-2108Asterisk: Mehrere SchwachstellenDeutsch2022-03-06csaf · cert_bundDE
Ein entfernter, authentisierter Angreifer kann mehrere Schwachstellen in Asterisk und Digium Certified Asterisk ausnutzen, um beliebigen Programmcode auszuführen, einen Denial of Service Zustand herbeizuführen oder Informationen offenzulegen.

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd fstec_bdu cert_bund nvd NVD CVE.org MITRE

published 2021-12-22modified 2026-06-17

related (720)

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+715 more

references (38)

External citations — patches, advisories, analysis.

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