Irontec sngrep up to 1.9.0 SIP Packet Validation sip_check_packet/sip_validate_packet off-by-one

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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5.9$0-$5k3.08

Summaryinfo

A vulnerability has been found in Irontec sngrep up to 1.9.0 and classified as critical. This vulnerability affects the function sip_check_packet/sip_validate_packet of the component SIP Packet Validation. Performing a manipulation results in off-by-one. This vulnerability is cataloged as CVE-2026-121943. It is possible to initiate the attack remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in Irontec sngrep up to 1.9.0. This affects the function sip_check_packet/sip_validate_packet of the component SIP Packet Validation. The manipulation with an unknown input leads to a off-by-one vulnerability. CWE is classifying the issue as CWE-193. A product calculates or uses an incorrect maximum or minimum value that is 1 more, or 1 less, than the correct value. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

Irontec sngrep through 1.9.0 contains an out-of-bounds stack read vulnerability in sip_check_packet and sip_validate_packet caused by an off-by-one length check on 10240-byte SIP payloads. Remote attackers can send a crafted UDP or TCP SIP packet or supply a pcap file to crash sngrep or leak adjacent stack bytes into displayed SIP fields.

The advisory is shared at github.com. This vulnerability is uniquely identified as CVE-2026-121943 since 11/04/2026. The exploitability is told to be easy. It is possible to initiate the attack remotely. No form of authentication is needed for exploitation. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 11/04/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-116900). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Vendor

Name

Version

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 6.1
VulDB Meta Temp Score: 5.9

VulDB Base Score: 7.3
VulDB Temp Score: 7.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA Base Score: 4.8
CNA Vector (VulnCheck): 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Off-by-one
CWE: CWE-193 / CWE-189
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

11/04/2026 Advisory disclosed
11/04/2026 +0 days CVE reserved
11/04/2026 +0 days VulDB entry created
11/04/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Not defined

CNA: VulnCheck
CVE: CVE-2026-121943 (🔒)

GCVE (CVE): GCVE-0-2026-121943
GCVE (VulDB): GCVE-100-431049
EUVD: 🔒

Entryinfo

Created: 11/04/2026 13:41
Updated: 11/04/2026 14:30
Changes: 11/04/2026 13:41 (75), 11/04/2026 14:30 (2)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Discussion

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