No exploitation reportedFix available

CVE-2023-37457

No exploitation reported by the sources we read.

Published2023-12-14
WeaknessCWE-120

Am I affected?

With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.

Description

Asterisk is an open source private branch exchange and telephony toolkit. In Asterisk versions 18.20.0 and prior, 20.5.0 and prior, and 21.0.0; as well as ceritifed-asterisk 18.9-cert5 and prior, the 'update' functionality of the PJSIP_HEADER dialplan function can exceed the available buffer space for storing the new value of a header. By doing so this can overwrite memory or cause a crash. This is not externally exploitable, unless dialplan is explicitly written to update a header based on data from an outside source. If the 'update' functionality is not used the vulnerability does not occur. A patch is available at commit a1ca0268254374b515fa5992f01340f7717113fa.

Timeline

dates in UTC

2023-12-1420:15CVE publishedNVD

Observed activity

isMalicious corpus · updated 2026-10-23 21:37 UTC

Indicators tagged with this CVE, per day0 indicators over 7 days

Block these indicators

Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2023-37457?format=txt
CSV export: https://api.ismalicious.com/edl/cve/CVE-2023-37457?format=csv
TAXII collection of exploited CVEs
The EDL and CSV take an API key on the Pro plan.

Versions per branch

NVD

Digium asterisk

Branch	Affected	Fixed in	Source
18.20	≤ 18.20.0	no fix published	NVD
20.5	≥ 19.0.0, ≤ 20.5.0	no fix published	NVD
21.0	= 21.0.0	no fix published	NVD

Sangoma certified asterisk

Branch	Affected	Fixed in	Source
13.13	= 13.13.0	no fix published	NVD
16.8	= 16.8.0	no fix published	NVD
18.9	= 18.9	no fix published	NVD

as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.

Fix

Advisories and patches

github.comPatch
github.comVendor Advisory

Detection

Nuclei template: none so far
Exploit-DB: no entry
Proof-of-concept repositories: none listed

Sources

CNACVSS 3.17.5read 2026-10-23
NVDCVSS 3.18.2read 2026-10-23
CNAweakness (CWE)CWE-120read 2026-10-23
NVDweakness (CWE)CWE-120read 2026-10-23
FIRST EPSSEPSS score1.1 %2026-10-22

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H
Published: 2023-12-14
Last Modified: 2026-06-17
NVD status: Modified

Frequently asked questions

What is CVE-2023-37457?

Is CVE-2023-37457 actively exploited?

Active exploitation of CVE-2023-37457 has not been confirmed. Its EPSS score was 1.1% on 2026-10-22, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2023-37457?

CVE-2023-37457 has a CVSS v3 base score of 8.2 (HIGH severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:H.

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