CVE-2026-63182

HIGHPre-NVD 8.18.1
EchelonGraph scoreLOW confidence

This high-severity CVE scores 8.1 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.2% (4th percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from a secondary CVSS source
Sources: a secondary CVSS source
Trending — 4 sources updated this week

Also known asEUVD-2026-114520 (ENISA EUVD)Source: ENISA EUVD

8.1EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (the SSVC decision on this page).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.2%CVSS: 8.1Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

LightSAML implements SAML 2.0 data model classes, XML serialization and deserialization, XML security, certificate support, and message bindings. Prior to 4.7.1 and 5.0.1, LightSAML and xmlseclibs disagree about which assertion an inbound SAML signature covers. Response::deserialize uses manyElementsFromXml to collect only direct-child saml:Assertion elements of samlp:Response, and AssertionSignatureValidatorAction validates their ds:Signature using an out-of-band trusted IdP credential resolved by Issuer, not a key from the document. XMLSecurityDSig::validateReference() removes the enveloped signature from the shared DOM, but processRefNode() resolves Reference URI="#id" document-wide through an XPath of the form //*[@Id] and takes item(0), which need not be the assertion whose claims LightSAML consumes. An attacker who has captured one genuinely signed assertion, such as an earlier login response, can place its signature-stripped bytes earlier in samlp:Extensions and present a forged direct-child assertion with the same ID and copied genuine signature. Validation then covers the hidden genuine bytes while LightSAML surfaces unsigned attacker-controlled Subject/NameID, Conditions, and Attributes, enabling authentication bypass or privilege escalation even when signature validation is required. The behavior was confirmed in versions 5.0.0 and 4.6.1. This issue is fixed in versions 4.7.1 and 5.0.1.

CVSS v3
8.1
EG Score
8.1HIGHlow confidence
EG Risk
36
EG Risk 36/100

EG Risk is EchelonGraph's 0–100 priority score. It fuses impact severity (EG Severity, the CVSS base score, never the KEV-floored or EPSS-lifted EG Score) with real-world exploitation and automatability, under weights EchelonGraph set by hand, so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner.

How it’s computed (value × EchelonGraph’s weight)
Severity81% × 45%
Impact severity (EG Severity): CVSS 8.1 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0% × 40%
No KEV listing, EG-KEV tier or EPSS when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's BOD 26-04 default: no one has published Automatable for this CVE, and CISA treats it as “no” for a CVE not in KEV.
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE.
Action: A fix is available. Apply it within your standard update timelines.
EPSS PROB
0.2%
EPSS %ILE
4th
KEV
Not listed

What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)

The EG score (8.1): severity, escalated by confirmed exploitation. This CVE's 8.1 is its impact severity (EG Severity), not escalated.

EG Severity
8.1 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.a secondary CVSS source · CVSS v3.0 or v3.1
EG Likelihood
0.2% within 30 daysSource: FIRST EPSS. FIRST's exploitation probability, not an EchelonGraph model.
Confirmed exploitation
None on record (CISA KEV, EG-KEV Tier 1)Reported apart from the likelihood: an observed fact, not a probability.
EG Priority
SSVC Track at medium mission impactTrack at low or medium mission impact; Track* at high (mission-essential systems).CISA BOD 26-04: 14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.Each input and its source, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

A fix is available. Apply it within your standard update timelines.

Exploitation none (no CISA value, KEV listing or exploit code on record) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). EchelonGraph holds no SSVC assessment of this CVE from CISA: none of these inputs is from Vulnrichment. EchelonGraph applied CISA's decision table to them; CISA publishes SSVC inputs and the table, not a decision for each CVE. Mission impact is CISA's Mission & Well-being decision point, and only you can judge it. CISA's table makes it high when Mission Prevalence is Essential — the vulnerable component "directly provides capabilities that constitute at least one MEF for at least one entity" (MEF: mission essential function) — or when Public Well-Being Impact is Irreversible: "multiple fatalities are likely", the cyber-physical system "is likely lost or destroyed", "extreme or serious externalities" are imposed on other parties, or social systems such as elections or the financial grid "are destabilized and potentially collapse". CISA's decision table

BOD 26-04 (CISA's remediation timeline, Table 1)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

The score's inputs: In CISA KEV no (CISA's KEV catalog) · Automatable no (CISA's BOD 26-04 default) · Technical impact total (CISA's BOD 26-04 default). Where an input reads “CISA's BOD 26-04 default”, no one has published it for this CVE, and CISA's implementation guidance says: “If “Automatable” and “Technical Impact” information items about a CVE ID are not available and the CVE ID is not in the KEV Catalog, CISA will treat its values as “no” and “total,” respectively, until CISA or a third party provides metadata about the CVE ID. CISA will always provide the Vulnrichment data for a CVE ID listed in the KEV Catalog.” Whether your system is publicly exposed is yours to answer. BOD 26-04 binds US Federal Civilian Executive Branch agencies; for anyone else it is CISA's published timeline, a reference rather than an obligation. The directive · how EchelonGraph applies it

Published

October 30, 2026

Last Modified

October 30, 2026

Advisory Details (7)

Auto-updated Oct 30, 2026
🔬 Proof of concept available. Patch available. Sources: github_commit, github_release, github, github_pr.
GitHub release Patch Available

5.0.1

Patch available: litesaml/lightsaml 5.0.1

https://github.com/litesaml/lightsaml/releases/tag/5.0.1
GitHub release Patch Available

4.7.1

Patch available: litesaml/lightsaml 4.7.1

https://github.com/litesaml/lightsaml/releases/tag/4.7.1
GitHub commit Patch Available

commit 3af82bf2f386 (litesaml/lightsaml)

Patch available: litesaml/lightsaml 4.7.1 (contains commit 3af82bf2f386)

https://github.com/litesaml/lightsaml/commit/3af82bf2f3865e6aafeeb1a97c97b383b8bb7b00
GitHub commit Patch Available

commit 230e62d1325f (litesaml/lightsaml)

Patch available: litesaml/lightsaml 5.0.1 (contains commit 230e62d1325f)

https://github.com/litesaml/lightsaml/commit/230e62d1325f2cbcaac814b78409775f7a8806a2
GitHub pull request Patch Available

fix: reject XML Signature Wrapping attacks in SignatureXmlReader (4.x backport)

Patch available: litesaml/lightsaml 4.7.1 (PR #122 merged 2026-09-10)

https://github.com/litesaml/lightsaml/pull/122
GitHub pull request Patch Available

fix: reject XML Signature Wrapping (XSW) attacks in SignatureXmlReader

Patch available: litesaml/lightsaml 5.0.1 (PR #113 merged 2026-06-29)

https://github.com/litesaml/lightsaml/pull/113
GitHub advisoryMentions a patch (unverified)🟡 PoC Available

Signature wrapping bypass · Advisory · litesaml/lightsaml · GitHub

https://github.com/litesaml/lightsaml/security/advisories/GHSA-w553-pwx6-3mg9

Weakness Classification(1)

MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.

Data Freshness Timeline

(refreshed 6× in last 7d / 6× in last 30d)

Each row is a time one of our pipelines fetched, updated or re-scored this CVE. For example, "NVD update" means NVD published or revised its analysis for this CVE; "MITRE cvelistV5" means we ingested or refreshed it from the CNA feed. An arrow marks a change the record states ("CVSS v3 → 9.1"); EPSS and GHSA rows show the values recorded at that time, not what changed (EPSS values are rounded; hover one for the exact figures). Most recent first.

  1. 2026-11-01 16:35 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  2. 2026-10-31 16:33 UTCEPSS rescoreEPSS 0.2% · 4th percentile
  3. 2026-10-30 23:02 UTCENISA EUVD ID recordedEUVD-2026-114520 · Source: ENISA EUVD
  4. 2026-10-30 22:26 UTCEG score recompute
  5. 2026-10-30 21:49 UTCEG score recomputeFirst assessed: 8.1 HIGH
  6. 2026-10-30 21:48 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-63182?
CVE-2026-63182 is a high-severity vulnerability; its CVE record was published on October 30, 2026. LightSAML implements SAML 2.0 data model classes, XML serialization and deserialization, XML security, certificate support, and message bindings. Prior to 4.7.1 and 5.0.1, LightSAML and xmlseclibs disagree about which assertion an inbound SAML signature covers. Response::deserialize uses…
When was the CVE record for CVE-2026-63182 published?
The CVE record for CVE-2026-63182 was published on October 30, 2026. That is the record's publication date; the vulnerability itself may have been made public earlier. EchelonGraph's copy of the record carries a last-modified date of October 30, 2026; the record at its source may have been updated since.
Is CVE-2026-63182 actively exploited?
CVE-2026-63182 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.2% probability of exploitation in the next 30 days (4th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-63182?
CVE-2026-63182 has a CVSS base score of 8.1 (a secondary CVSS source that NVD displays; NVD's own analysis pending). The EG score is currently aggregating — additional source signals are being incorporated as they become available..
How do I remediate CVE-2026-63182?
A fix for CVE-2026-63182 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

Explore the affected products and dependency analysis for CVE-2026-63182

Explore →

Is Your Infrastructure Affected by CVE-2026-63182?

EchelonGraph automatically scans your cloud infrastructure and maps CVE exposure using blast radius analysis.