CVE-2026-90558

sngrep through 1.8.4 Stack Buffer Overflow via SIP Headers

Published Sep 12, 2026 CVSS 4.0 · 9.3 Critical EPSS < 1% KEV · Not listed

Description

sngrep through 1.8.4 contains stack buffer overflow vulnerabilities in SIP attribute formatting routines when header values exceed the 255-byte buffer limit. Attackers can craft malicious SIP packets with oversized Call-ID, X-Call-ID, or other header fields to overflow stack buffers and cause crashes or execute arbitrary code during packet parsing and rendering.

Analysis

Technical impact

sngrep, a network traffic monitoring tool, contains an unchecked stack buffer in its SIP attribute formatting routines. When SIP header values exceed the 255‑byte limit, the application can overflow the stack while parsing incoming packets. An attacker can craft SIP packets with oversized Call‑ID, X‑Call‑ID, or other header fields, causing the process to crash or potentially execute arbitrary code during rendering.

Affected Systems

The flaw affects irontec sngrep version 1.8.4. Any deployment that receives or processes SIP traffic with this version is susceptible to the overflow.

Risk and Exploitability

The vulnerability carries a CVSS score of 9.3, indicating critical severity. EPSS data indicates a very low exploitation probability (< 1 %), yet the flaw is reachable over the network and does not require local privileges. The issue is not listed in the CISA KEV catalog, but the combination of high severity and network accessibility makes timely remediation essential.

Affected Products

Default status is the baseline for the product, each version can override it (e.g. patched versions marked unaffected).

Vendor Product Default status Versions

irontec

sngrep

unaffected

Version	Status	Constraints
`0`	affected	≤ 1.8.4

No data.

Vendor Product Versions

Irontec

Sngrep

Version	Status	Scheme	Platform
`[0,1.8.4]`	affected	generic	—

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

Apply the vendor‑supplied patch referenced by commit 1ff74ee3ab5ff280e8ba976aa8c744dca57eb35b, which adds bounds checking on SIP header values and mitigates the stack‑based buffer overflow identified as CWE‑121.
Upgrade to the latest sngrep release that includes the fixed code, ensuring all buffer‑bound checks are updated.
Configure network filtering or firewall rules to block or drop SIP packets whose header fields exceed 255 bytes until a patch is applied, reducing exposure to the CWE‑121 vulnerability.

Generated by OpenCVE AI on September 21, 2026 at 13:25 UTC.

Tracking

Advisories

No advisories available

Metrics

Attack Vector Network

Attack Complexity Low

Privileges Required None

Attack Requirements None

User Interaction None

Vulnerable System Confidentiality Impact High

Vulnerable System Integrity Impact High

Vulnerable System Availability Impact High

Subsequent System Confidentiality Impact None

Subsequent System Integrity Impact None

Subsequent System Availability Impact None

Attack Vector Network

Attack Complexity Low

Privileges Required None

Scope Unchanged

Confidentiality Impact High

Integrity Impact High

Availability Impact High

User Interaction None

No CVSS v3.0

No CVSS v2

This CVE is not in the KEV list.

Exploit prediction score: < 1% (0.879% probability within 30 days)

Exploitation none

Automatable no

Technical Impact total

References

Link	Providers
https://github.com/irontec/sngrep
https://github.com/irontec/sngrep/blob/v1.8.4/src/sip_call.c#L260
https://github.com/irontec/sngrep/blob/v1.8.4/src/sip_msg.c#L150
https://github.com/irontec/sngrep/commit/1ff74ee3ab5ff280e8ba976aa8c744dca57eb35b
https://www.cve.org/CVERecord?id=CVE-2026-90558
https://www.vulncheck.com/advisories/sngrep-through-1.8.4-stack-buffer-overflow-via-sip-headers

History

Sep 21, 2026 12:15 PM Weaknesses updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Weaknesses		CWE-120
References		https://www.cve.org/CVERecord?id=CVE-2026-90558
Metrics	threat_severity `None`	threat_severity `Critical`

Sep 14, 2026 9:00 PM Scoring metrics updated View changes

Type	Values Removed	Values Added
Metrics		ssvc `{'options': {'Automatable': 'no', 'Exploitation': 'none', 'Technical Impact': 'total'}, 'version': '2.0.3'}`

Sep 12, 2026 6:15 PM Description updated. Title updated. First appearance in the feed. Weaknesses updated. Affected versions updated. Affected vendors updated. Added references. Scoring metrics updated View changes

Type	Values Removed	Values Added
Description		sngrep through 1.8.4 contains stack buffer overflow vulnerabilities in SIP attribute formatting routines when header values exceed the 255-byte buffer limit. Attackers can craft malicious SIP packets with oversized Call-ID, X-Call-ID, or other header fields to overflow stack buffers and cause crashes or execute arbitrary code during packet parsing and rendering.
Title		sngrep through 1.8.4 Stack Buffer Overflow via SIP Headers
First Time appeared		Irontec Irontec sngrep
Weaknesses		CWE-121
CPEs		cpe:2.3:a:irontec:sngrep::::::::
Vendors & Products		Irontec Irontec sngrep
References		https://github.com/irontec/sngrep https://github.com/irontec/sngrep/blob/v1.8.4/src/sip_call.c#L260 https://github.com/irontec/sngrep/blob/v1.8.4/src/sip_msg.c#L150 https://github.com/irontec/sngrep/commit/1ff74ee3ab5ff280e8ba976aa8c744dca57eb35b https://www.vulncheck.com/advisories/sngrep-through-1.8.4-stack-buffer-overflow-via-sip-headers
Metrics		cvssV3_1 `{'score': 9.8, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H'}` cvssV4_0 `{'score': 9.3, 'vector': 'CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N'}`