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Fencer Vulns
medium 4.5

CVE-2023-28096 json

OpenSIPS has memory leak in cJSON lib

published 2023-03-15 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-31821

cvss
4.5
version 3.1, CNA
cisa kev
Not listed
not in CISA's catalog
epss
0.8%
EPSS 0.8% chance of exploitation in 30 days, percentile 55%
public exploits
0
none known

Summary

OpenSIPS, a Session Initiation Protocol (SIP) server implementation, has a memory leak starting in the 2.3 branch and priot to versions 3.1.8 and 3.2.5. The memory leak was detected in the function `parse_mi_request` while performing coverage-guided fuzzing. This issue can be reproduced by sending multiple requests of the form `{"jsonrpc": "2.0","method": "log_le`. This malformed message was tested against an instance of OpenSIPS via FIFO transport layer and was found to increase the memory consumption over time.

To abuse this memory leak, attackers need to reach the management interface (MI) which typically should only be exposed on trusted interfaces. In cases where the MI is exposed to the internet without authentication, abuse of this issue will lead to memory exhaustion which may affect the underlying system’s availability. No authentication is typically required to reproduce this issue. On the other hand, memory leaks may occur in other areas of OpenSIPS where the cJSON library is used for parsing JSON objects.

The issue has been fixed in versions 3.1.8 and 3.2.5.

Patch / fix

  • opensips opensips 3.1.8, 3.2.5

CISA SSVC

Exploitation
none
Automatable
no
Technical impact
partial
Assessed
20 mo ago

Exploit prediction

0.77% chance of exploitation in the next 30 days, higher than 55% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by version score vector
CNA 3.1 4.5 CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:N/I:N/A:H
NVD 3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Affected products

  • OpenSIPS opensips

Classification

Weakness
  • CWE-401 Missing Release of Memory after Effective Lifetime

References

Sources

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.