CVEvulnerability

CVE-2026-49840

9.1 CRITICAL Published 2026-06-09 Modified 2026-07-23 Official page ↗
Status
Analyzed
Published
2026-06-09
Last modified
2026-07-23
Assigner
[email protected]
CVSS 3.1 ([email protected])
9.1 CRITICAL — CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
Weaknesses
CWE-122, CWE-195, CWE-20, CWE-787

Description

FreeSWITCH is a Software Defined Telecom Stack enabling the digital transformation from proprietary telecom switches to a software implementation that runs on any commodity hardware. Prior to version 1.11.1, esl_recv_event() parses Content-Length with atol() and passes the result straight to malloc(len + 1) with no sign or magnitude check. A malicious or man-in-the-middle ESL peer can send a frame with a negative Content-Length to corrupt the heap of, or crash, any process linked against libesl, before the client has authenticated to that peer. This issue has been patched in version 1.11.1.

Affected configurations

• freeswitch freeswitch (< 1.11.1)

Related

Weakness · CWE (4)

  • CWE-122 Heap-based Buffer Overflow weakness
  • CWE-195 Signed to Unsigned Conversion Error weakness
  • CWE-20 Improper Input Validation weakness
  • CWE-787 Out-of-bounds Write weakness

References