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Threats / IETF / CVE-2023-29552
CVE-2023-29552 · EUVD no mirror located · GCVE no mirror located Verified 2026-08-04

IETF Service Location Protocol (SLP) vulnerability

Service Location Protocol (SLP) contains a denial-of-service vulnerability allowing unauthenticated remote attackers to register services and conduct amplified DoS attacks via spoofed UDP traffic.

Verdict

Today item — known-exploited.

An unauthenticated remote attacker can exploit SLP's service registration mechanism and UDP amplification properties to launch denial-of-service attacks against targeted systems without authentication requirements.

CISA KEV Yes · 2023-11-084EPSS 0.65873 (verify live)5Exploit Public PoC6CVSS 7.5 (CISA)3CISA SSVC Exploitation: active · Automatable: yes · Impact: partial3
01

Is it exploitable?

— the evidence, ranked above the score
Exploit available
Public proof-of-concept exploit code is cataloged for this vulnerability.We link the existence of the exploit; we do not host or redistribute payloads.
Reported exploitation
3 independent public reports of in-the-wild exploitation are cataloged.Distinct reporting sources (vendor, incident response, government); open them for the underlying claims.
Exploited in the wild
Listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-11-08).
CISA KEV ↗Confirmed
Probability (EPSS)
EPSS 0.65873 — modeled likelihood of exploitation activity.EPSS is a daily-changing model output — open the source for today's value.
Severity / affected
CVSS 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) · Affected: IETF, Service Location Protocol (SLP). Confirm exact fixed builds in the vendor advisory.CVSS — CISA-assigned via the ADP container (CVE.org), version 3.1; the CNA left no metrics, so CISA's own score is used ahead of NVD.
CISA-ADP ↗Reported
CISA SSVC (triage disposition)
Exploitation: active · Automatable: yes · Technical Impact: partialCISA's own stakeholder-specific triage inputs, published in the CVE record (CISA Coordinator role). NOTE: this is CISA's three decision points; the final Act/Attend/Track decision also requires a Mission & Well-being input not published here, so no overall decision is asserted.
CISA-ADP ↗Reported
Currency of the record
CISA added this to its KEV catalog 197 days after the CVE record was published.KEV lag = CISA-KEV dateAdded − CVE.org datePublished; a floor on how long the known-exploited flaw sat in the public record before the federal catalog listed it. Severity/weakness here is CNA- or CISA-assigned (current at disclosure), independent of NVD's analysis backlog.
02

Who’s exploiting it?

— attribution turns risk into urgency
Attribution not established

No confirmed (advisory-backed) threat-actor attribution is established for this record. Absence of a named actor is not absence of compromise — see Coverage & confidence.

03

Why it matters

— the attack path, told twice: adversary, then board
1

Front door — unauthenticated access narrative 1

Attacker
I register malicious services in the SLP directory using spoofed UDP packets to amplify my attack traffic.
Business
Service availability degrades as legitimate SLP queries are overwhelmed by amplified attack traffic, disrupting network operations.
2

Keys to the kingdom — privilege/identity takeover narrative 2

Attacker
I direct amplified responses toward victim infrastructure by exploiting SLP's UDP-based protocol design and lack of authentication controls.
Business
Network bandwidth is consumed by volumetric attacks, potentially affecting multiple services and customer connectivity.
04

What to do

— defensible action
  • Remediate per the vendor advisory — confirm the fixed build for your version and verify exposure.1
Say it to the boardA vulnerability with this evidence profile is a defensible budget line, not a backlog ticket — fund the change against the proof above.
05

Coverage & confidence

— what we know, and what we don’t

Established (cited)

  • KEV listing (CISA)
  • EPSS probability (FIRST)
  • Public PoC available (VulnCheck)
  • 3 reported-exploitation source(s)
  • CVSS 7.5 — CISA-assigned (CVE.org ADP)
  • CISA SSVC triage disposition (CVE.org ADP)
  • Public exploit availability
  • Catalogued by mitre (CNA)
  • Coverage gaps — stated, not hidden

  • No EUVD / GCVE mirror in feed — single-authority dependency for the identifier.
  • EPSS & exposure are time-varying; verify live at the source.
  • Threat-actor attribution not established from feed data — absence of a name is not absence of compromise.
  • No finder/reporter credit recorded in the public CVE entry — the work behind this find is unattributed.
  • Disclosure & credit2
    Catalogued by mitreCNA
    Credited with finding itNo finder named in the public CVE record — the work behind this find is unattributed.