Exploited

CVE-2023-29552

Protocoles (IETF) Service Location Protocol (SLP) · Frameworks and libraries

Service Location Protocol (SLP) Denial-of-Service Vulnerability

At a glance

Exploited. Added to CISA’s catalog of exploited vulnerabilities on November 8, 2023.

Affected product: Protocoles (IETF) Service Location Protocol (SLP) (category Frameworks and libraries, indicative classification). Name in CISA’s catalog: IETF Service Location Protocol (SLP).

What should I do?

CISA has issued a specific required action for this vulnerability: read its original text below.

Deadline set by CISA for US federal agencies: 21 days (due November 29, 2023). It only binds those agencies, but it is a useful measure of urgency.

The vendor’s specific advisory is listed in the NVD references: CVE-2023-29552 on the NVD website.

Original text of the required action (CISA)

Apply mitigations per vendor instructions or disable SLP service or port 427/UDP on all systems running on untrusted networks, including those directly connected to the Internet.

Timeline

April 25, 2023 Vulnerability published Publication date (NVD)
November 8, 2023 Exploitation confirmed Added to CISA’s KEV catalog
November 29, 2023 CISA deadline Remediation deadline set for US federal agencies

The facts, with their sources

Exploitation confirmed: Yes, on November 8, 2023 Date added to the catalog of exploited vulnerabilities. Exploitation itself may have started earlier. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Ransomware: No known use to date That does not guarantee it is not being used: the information is not public. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Hunt for compromise: Not requested by CISA Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA required action: Specific action (original text above) Rewritten by this site from CISA’s original text. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CISA deadline: November 29, 2023, 21 days Set for US federal agencies: a measure of urgency, not an obligation elsewhere. Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
Vulnerability published: April 25, 2023 Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC
Product according to CISA: IETF Service Location Protocol (SLP) Filed by this site under “Frameworks and libraries” (indicative classification). Source: KEV catalog, collected September 29, 2026 at 14:57 UTC
CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Technical detail of the score: attack vector, complexity, impact. Source: National Vulnerability Database (NVD), collected September 29, 2026 at 15:00 UTC

Severity and activity

7.5 / 10 CVSS severity: high

Score from the NVD. Collected Sep 29, 2026.

— Probability of exploitation in the next 30 days (EPSS)

FIRST’s EPSS model. Since exploitation is already confirmed, this figure is mostly useful to compare activity. Collected Sep 29, 2026.

Description

The Service Location Protocol (SLP, RFC 2608) allows an unauthenticated, remote attacker to register arbitrary services. This could allow the attacker to use spoofed UDP traffic to conduct a denial-of-service attack with a significant amplification factor.

The Service Location Protocol (SLP) contains a denial-of-service (DoS) vulnerability that could allow an unauthenticated, remote attacker to register services and use spoofed UDP traffic to conduct a denial-of-service (DoS) attack with a significant amplification factor.

Summary from CISA (KEV catalog).

CERT-FR advisories

No advisory among the latest CERT-FR publications this site follows. That does not mean there are none.

Information reused under the Open Licence 2.0 (Etalab); the date of last update is shown for each advisory. This site is neither affiliated with nor endorsed by ANSSI.

Sources for this page

CISA KEV catalog: exploitation, date added, required action, deadline, ransomware.
NVD (NIST): CVSS severity, publication date, description, vendor references.
EPSS (FIRST): probability of exploitation.
CERT-FR: advisories and alerts (in French).
Brand and category: indicative classification by this site (method).