High severity · published Oct 26, 2026
CVE-2026-57187
Asterisk: Heap-use-after-free in Asterisk PJSIP TCP/SDP handling when TCP connection closes during SDP processing
New
7.1
CVSS
0.5%
EPSS
No
On KEV
Description
Asterisk is an open source private branch exchange and telephony toolkit. Prior to Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3, an authenticated attacker may cause a heap-use-after-free in `PJSIP TCP/SDP` handling by sending a `SIP INVITE` over a connection-oriented transport and disconnecting before Asterisk responds with the `200 OK`. So far, the crash has only been reproduced when Asterisk is built with `Address Sanitizer`, which detects the issue. `Address Sanitizer` is a development tool with significant performance overhead and, according to the maintainer, is not used in production systems. This issue is fixed in Asterisk 20.20.1, 21.12.3, 22.10.1, 23.4.1 and Certified Asterisk 20.7-cert11, 22.8-cert3.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 41% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AS
asterisk · asterisk
< 20.20.1; >= 21.0.0-pre1, < 21.12.3; >= 22.0.0-pre1, < 22.10.1; >= 23.0.0-pre1, < 23.4.1 · source: vendor
CE
certified-asterisk · asterisk
< 20.7-cert11; >= 22.8-cert1-pre1, < 22.8-cert3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-57187
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-57187
github.com
https://github.com/asterisk/asterisk/commit/0f076168e0be31ebee37762192d0ee049e9c0d42
github.com
https://github.com/asterisk/asterisk/commit/27b9544b32f059a4f614169243eaa7559f622aa0
github.com
https://github.com/asterisk/asterisk/commit/6e1f4df744369d66ea6f412e355d819b2a7bf26c
github.com
https://github.com/asterisk/asterisk/commit/9e0386c6d259f0c7499d52499d9891bee8a494fa
github.com
https://github.com/asterisk/asterisk/commit/b7ba85458796ef54b471017287c7806095dbda76
github.com
https://github.com/asterisk/asterisk/commit/d4e30005940f86942745bcc64f34748d69870247
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