How severe is CVE-2023-27599?

CVE-2023-27599 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.

Is CVE-2023-27599 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-27599?

CVE-2023-27599 affects Opensips. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2023-27599?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.

When was CVE-2023-27599 published?

CVE-2023-27599 was published on 2023-03-15 and last updated on 2026-06-17.

CVE-2023-27599

CVE-2023-27599 is a high-severity vulnerability in Opensips with a CVSS 3.x base score of 7.5. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-20.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (58th percentile)
Actively exploited: Not listed in CISA KEV
Weakness: CWE-20
Affected product: Opensips
Published: 2023-03-15
Last modified: 2026-06-17

Description

OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Prior to versions 3.1.7 and 3.2.4, when the function `append_hf` handles a SIP message with a malformed To header, a call to the function `abort()` is performed, resulting in a crash. This is due to the following check in `data_lump.c:399` in the function `anchor_lump`. An attacker abusing this vulnerability will crash OpenSIPS leading to Denial of Service. It affects configurations containing functions that make use of the affected code, such as the function `append_hf`. This issue has been fixed in versions 3.1.7 and 3.2.4.

Frequently asked questions

What is CVE-2023-27599?: OpenSIPS is a Session Initiation Protocol (SIP) server implementation. Prior to versions 3.1.7 and 3.2.4, when the function `append_hf` handles a SIP message with a malformed To header, a call to the function `abort()` is performed, resulting in a crash. This is due to the following check in `data_lump.c:399` in the function `anchor_lump`. An attacker abusing this vulnerability will crash OpenSIPS leading to Denial of Service. It affects configurations containing functions that make use of the affected code, such as the function `append_hf`. This issue has been fixed in versions 3.1.7 and 3.2.4.
How severe is CVE-2023-27599?: CVE-2023-27599 has a CVSS 3.x base score of 7.5, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
Is CVE-2023-27599 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (58th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-27599?: CVE-2023-27599 affects Opensips. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2023-27599?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
When was CVE-2023-27599 published?: CVE-2023-27599 was published on 2023-03-15 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:opensips:opensips:*:*:*:*:*:*:*:*

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