How severe is CVE-2023-52557?

CVE-2023-52557 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-2023-52557 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2023-52557?

CVE-2023-52557 primarily affects Openbsd. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.

How do I fix CVE-2023-52557?

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.

Does CVE-2023-52557 have an EU (EUVD) identifier?

Yes. CVE-2023-52557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-57181.

When was CVE-2023-52557 published?

CVE-2023-52557 was published on 2024-03-01 and last updated on 2026-06-17.

CVE-2023-52557

CVE-2023-52557 is a high-severity vulnerability in Openbsd 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-131.

Key facts

Severity: High (CVSS 3.x base score 7.5)
EPSS exploit prediction: 1% (42nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2023-57181
Weakness: CWE-131
Affected product: Openbsd
Published: 2024-03-01
Last modified: 2026-06-17

Description

In OpenBSD 7.3 before errata 016, npppd(8) could crash by a l2tp message which has an AVP (Attribute-Value Pair) with wrong length.

Frequently asked questions

What is CVE-2023-52557?: In OpenBSD 7.3 before errata 016, npppd(8) could crash by a l2tp message which has an AVP (Attribute-Value Pair) with wrong length.
How severe is CVE-2023-52557?: CVE-2023-52557 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-2023-52557 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (42nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2023-52557?: CVE-2023-52557 primarily affects Openbsd. In total, 17 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
How do I fix CVE-2023-52557?: 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.
Does CVE-2023-52557 have an EU (EUVD) identifier?: Yes. CVE-2023-52557 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2023-57181.
When was CVE-2023-52557 published?: CVE-2023-52557 was published on 2024-03-01 and last updated on 2026-06-17.

References

Affected products (17)

cpe:2.3:o:openbsd:openbsd:*:*:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:-:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_001:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_002:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_003:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_004:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_005:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_006:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_007:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_008:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_009:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_010:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_011:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_012:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_013:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_014:*:*:*:*:*:*
cpe:2.3:o:openbsd:openbsd:7.3:errata_015:*:*:*:*:*:*

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