CVE-2026-104844

MEDIUMPre-NVD 5.95.9
EchelonGraph scoreMEDIUM confidence

“—” beside the score: it is equal to the CVSS score beside it.

Score 5.9 from GitHub Security Advisory (severity: MODERATE) published 2026-10-05. A secondary CVSS source baseline 5.9; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, a secondary CVSS source

Also known asEUVD-2026-91741 (ENISA EUVD) · GHSA-rj75-hqrm-r3gf (GitHub Security Advisories)Source: ENISA EUVD

5.9EG
EchelonGraph verdictMonitorRemediate within your standard update timelines (the SSVC decision on this page).
  • Lower severity and no public exploit yet
CISA-KEV: Not listedEPSS PROB: 0.4%CVSS: 5.9Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

PostCSS Selector Parser is a CSS selector parser that integrates with PostCSS but does not require it. Prior to 7.1.6, src/parser.js splitWord() can receive a flat selector as one word token carrying many class or ID indexes because period and hash characters are not tokenizer word delimiters. The uniqs() deduplication and per-index class and ID membership checks repeatedly scan the class and ID index arrays, while a separate Sass-interpolation filtering pass also performs repeated linear scanning. Together, these passes make parsing quadratic in the number of indexes and allow a crafted selector to occupy a synchronous parser thread. The maxNestingDepth guard does not mitigate the issue because the hostile selector can have zero nesting depth. Only consumers that synchronously parse untrusted selectors in an exposed request path are affected; ordinary build-time parsing of trusted sources is not affected. This issue is fixed in version 7.1.6.

CVSS v3
5.9
EG Score
5.9MEDIUMmedium confidence
EG Risk
27
EG Risk 27/100

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)
Severity59% × 45%
Impact severity (EG Severity): CVSS 5.9 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation0.4% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at every mission impact level.
Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (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
0.4%
EPSS %ILE
33rd
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 (5.9): severity, escalated by confirmed exploitation. This CVE's 5.9 is its impact severity (EG Severity), not escalated.

EG Severity
5.9 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
0.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-04). 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 every mission impact level.CISA BOD 26-04: 60 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 every mission impact level.

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

Exploitation none (CISA Vulnrichment) · Automatable no (CISA Vulnrichment) · Technical impact partial (CISA Vulnrichment). All three are CISA's SSVC values (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)60 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 Vulnrichment) · Technical impact partial (CISA Vulnrichment). 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 2, 2026

Last Modified

October 2, 2026

Advisory Details (3)

Auto-updated Oct 2, 2026
Patch available. Sources: github_commit, github_release, github.
GitHub release Patch Available

7.1.6

Patch available: postcss/postcss-selector-parser 7.1.6

https://github.com/postcss/postcss-selector-parser/releases/tag/7.1.6
GitHub commit Patch Available

commit 62b191792df0 (postcss/postcss-selector-parser)

Patch available: postcss/postcss-selector-parser 7.1.6 (contains commit 62b191792df0)

https://github.com/postcss/postcss-selector-parser/commit/62b191792df0a0bc56062e5a875bc74aae2a51cd
GitHub advisoryMentions a patch (unverified)

Quadratic complexity in flat selector parsing allows CPU exhaustion · Advisory · postcss/postcss-selector-parser · GitHub

Affected: 7.1.6. The three passes now use Set membership tests, making parsing

https://github.com/postcss/postcss-selector-parser/security/advisories/GHSA-rj75-hqrm-r3gf

Vendor Advisories for CVE-2026-104844(1)

These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.

Patch Availability(2)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
npmpostcss-selector-parser @ 7.1.6 (fixes >= 7.0.0, < 7.1.6)—ghsa
npmpostcss-selector-parser @ 6.1.5 (fixes < 6.1.5)—ghsa

Patches are aggregated from vendor advisories (Red Hat, Microsoft, Cisco, GitHub) and package ecosystems (OSV, GHSA). Multiple rows for the same upstream release have been deduplicated.

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
postcss-selector-parser—
  • 7.0.0 up to 7.1.6: fixed in 7.1.6
  • every version up to 6.1.5: fixed in 6.1.5
—

Weakness Classification(2)

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

Data Freshness Timeline

(refreshed 7× in last 7d / 33× 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 its CVE.org record (CNA or CISA ADP). 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). "EchelonGraph re-scored" is our own recompute of this CVE's score, not an update from a source, and is not counted in the refreshes above. Most recent first.

  1. 2026-11-13 16:50 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  2. 2026-11-12 16:32 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  3. 2026-11-11 16:37 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  4. 2026-11-10 16:41 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  5. 2026-11-09 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  6. 2026-11-08 16:38 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  7. 2026-11-07 16:38 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  8. 2026-11-06 16:35 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  9. 2026-11-05 16:36 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  10. 2026-11-04 22:56 UTCEchelonGraph re-scored
  11. 2026-11-04 22:56 UTCGHSA enrichmentGHSA-rj75-hqrm-r3gf · GitHub severity MODERATE · GitHub CVSS 5.9
  12. 2026-11-04 16:34 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  13. 2026-11-03 16:46 UTCEPSS rescoreEPSS 0.4% · 33rd percentile
  14. 2026-11-02 16:43 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  15. 2026-11-01 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  16. 2026-11-01 08:00 UTCGHSA enrichmentGHSA-rj75-hqrm-r3gf · GitHub severity MODERATE · GitHub CVSS 5.9
  17. 2026-11-01 08:00 UTCEchelonGraph re-scored
  18. 2026-10-31 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  19. 2026-10-31 11:55 UTCOSV refresh
  20. 2026-10-30 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  21. 2026-10-29 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  22. 2026-10-28 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  23. 2026-10-27 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  24. 2026-10-26 16:30 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  25. 2026-10-25 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
Show 40 more
  1. 2026-10-25 14:55 UTCEchelonGraph re-scored
  2. 2026-10-24 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  3. 2026-10-23 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  4. 2026-10-23 09:16 UTCEchelonGraph re-scored
  5. 2026-10-22 16:33 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  6. 2026-10-21 16:32 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  7. 2026-10-20 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  8. 2026-10-19 16:31 UTCEPSS rescoreEPSS 0.4% · 32nd percentile
  9. 2026-10-18 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  10. 2026-10-18 05:09 UTCEchelonGraph re-scored
  11. 2026-10-17 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  12. 2026-10-16 16:40 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  13. 2026-10-15 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  14. 2026-10-14 16:31 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  15. 2026-10-13 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  16. 2026-10-12 16:40 UTCEchelonGraph re-scored
  17. 2026-10-12 16:33 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  18. 2026-10-11 20:15 UTCEchelonGraph re-scored
  19. 2026-10-11 18:27 UTCEchelonGraph re-scored
  20. 2026-10-11 15:01 UTCEchelonGraph re-scored
  21. 2026-10-11 13:47 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  22. 2026-10-11 09:25 UTCEchelonGraph re-scored
  23. 2026-10-10 19:59 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  24. 2026-10-10 10:30 UTCEchelonGraph re-scored
  25. 2026-10-09 20:06 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  26. 2026-10-09 11:35 UTCEchelonGraph re-scored
  27. 2026-10-08 17:11 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  28. 2026-10-08 12:35 UTCEchelonGraph re-scored
  29. 2026-10-07 23:47 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  30. 2026-10-07 13:40 UTCEchelonGraph re-scored
  31. 2026-10-06 15:17 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  32. 2026-10-06 14:45 UTCEchelonGraph re-scored
  33. 2026-10-05 17:42 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  34. 2026-10-05 15:50 UTCEchelonGraph re-scored
  35. 2026-10-04 23:21 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  36. 2026-10-03 17:45 UTCEchelonGraph re-scored
  37. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.4% · 31st percentile
  38. 2026-10-02 16:27 UTCEchelonGraph re-scored
  39. 2026-10-02 15:56 UTCEchelonGraph re-scoredFirst assessed: 5.9 MEDIUM
  40. 2026-10-02 15:55 UTCMITRE cvelistV5first tracked

Frequently asked(5)

What is CVE-2026-104844?
CVE-2026-104844 is a medium-severity vulnerability; its CVE record was published on October 2, 2026. PostCSS Selector Parser is a CSS selector parser that integrates with PostCSS but does not require it. Prior to 7.1.6, src/parser.js splitWord() can receive a flat selector as one word token carrying many class or ID indexes because period and hash characters are not tokenizer word delimiters. The…
When was the CVE record for CVE-2026-104844 published?
The CVE record for CVE-2026-104844 was published on October 2, 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 2, 2026; the record at its source may have been updated since.
Is CVE-2026-104844 actively exploited?
CVE-2026-104844 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.4% probability of exploitation in the next 30 days (33rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-104844?
CVE-2026-104844 has a CVSS base score of 5.9 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-104844?
A fix for CVE-2026-104844 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-104844 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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