CVE-2026-44649

CRITICALPre-NVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

This critical-severity CVE scores 9.8 under a secondary CVSS source (NVD's own analysis pending). EPSS exploit probability: 0.3% (20th 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: EPSS, a secondary CVSS source
Elevated
9.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines at low or medium mission impact and sooner than that at high (the SSVC decision on this page).
  • CISA's Vulnrichment rates exploitation as PoC; EchelonGraph holds no exploit-code reference for it
CISA-KEV: Not listedEPSS PROB: 0.3%CVSS: 9.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

SillyTavern is a locally installed user interface that allows users to interact with text generation large language models, image generation engines, and text-to-speech voice models. Prior to 1.18.0, SillyTavern accepts Remote-User (Authelia) and X-Authentik-Username (Authentik) HTTP headers to automatically log in users when SSO is configured. There is no validation that these headers originate from a trusted reverse proxy. Any network client that can reach the SillyTavern port directly can inject these headers and authenticate as any user, including administrators, without a password. This vulnerability is exploitable only when sso.autheliaAuth: true or sso.authentikAuth: true is set in config.yaml (both default to false). This vulnerability is fixed in 1.18.0.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
75
EG Risk 75/100

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)
Severity98% × 45%
Impact severity (EG Severity): CVSS 9.8 of 10. Never the KEV-floored or EPSS-lifted EG Score.
Exploitation40% × 40%
EchelonGraph's fixed weight for EG-KEV Tier 3 (Elevated): a constant, not a probability.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low, Track* at medium and Attend at high mission impact.
Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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 at low or medium mission impact and sooner than that at high.
EPSS PROB
0.3%
EPSS %ILE
20th
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 (9.8): severity, escalated by confirmed exploitation. This CVE's 9.8 is its impact severity (EG Severity), not escalated.

EG Severity
9.8 CRITICALCVSS-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
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-19). 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, Track* at medium and Attend at high mission impact.CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days if it is not.Each input and its source: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low, Track* at medium and Attend at high mission impact.

A fix is available. Apply it within your standard update timelines at low or medium mission impact and sooner than that at high.

Exploitation public PoC (CISA Vulnrichment) · Automatable yes (CISA Vulnrichment) · Technical impact total (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)3 days if the affected system is publicly exposed; 60 days if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable yes (CISA Vulnrichment) · Technical impact total (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

May 29, 2026

Last Modified

July 22, 2026

Advisory Details (1)

Auto-updated Oct 16, 2026
🔬 Proof of concept available. Patch available. Sources: github.
GitHub advisoryMentions a patch (unverified)🟡 PoC Available

Authentication Bypass via SSO Header Injection · Advisory · SillyTavern/SillyTavern · GitHub

https://github.com/SillyTavern/SillyTavern/security/advisories/GHSA-gxx6-h3g6-vwjh

Vendor Advisories for CVE-2026-44649(1)

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

Affected Packages

(1 across 1 ecosystem)
npm(1)
PackageVulnerable rangeFix by version rangeDependents
sillytavern—
  • every version up to 1.18.0: fixed in 1.18.0
—

Weakness Classification(4)

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

Data Freshness Timeline

(refreshed 14× in last 7d / 36× 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.

Showing the most recent 100 of 182 refreshes on record for this CVE.

A repeat, a row identical to one the same pipeline wrote less than 10 seconds earlier, is not a separate refresh and is not counted. None are among the latest 100 rows. The 82 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-20 12:32 UTCEG score recompute
  2. 2026-10-19 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  3. 2026-10-19 13:17 UTCEG score recompute
  4. 2026-10-18 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  5. 2026-10-18 03:39 UTCEG score recompute
  6. 2026-10-17 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  7. 2026-10-17 13:32 UTCEG score recompute
  8. 2026-10-16 16:42 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  9. 2026-10-16 14:30 UTCEG score recompute
  10. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  11. 2026-10-15 14:56 UTCEG score recompute
  12. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  13. 2026-10-14 09:23 UTCEG score recompute
  14. 2026-10-13 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  15. 2026-10-13 06:50 UTCEG score recompute
  16. 2026-10-12 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  17. 2026-10-12 16:05 UTCEG score recompute
  18. 2026-10-11 19:47 UTCEG score recompute
  19. 2026-10-11 17:01 UTCEG score recompute
  20. 2026-10-11 14:27 UTCEG score recompute
  21. 2026-10-11 13:48 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  22. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  23. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  24. 2026-10-08 17:12 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  25. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 20th percentile
Show 75 more
  1. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  2. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  3. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  4. 2026-10-03 14:48 UTCOSV refresh
  5. 2026-10-03 14:25 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  6. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  7. 2026-09-30 15:03 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  8. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  9. 2026-09-26 15:58 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  10. 2026-09-23 17:53 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  11. 2026-09-20 20:15 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  12. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  13. 2026-09-17 19:31 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  14. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  15. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  16. 2026-09-14 06:24 UTCEG score recompute
  17. 2026-09-13 16:47 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  18. 2026-09-13 01:06 UTCOSV refresh
  19. 2026-09-12 15:01 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  20. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  21. 2026-09-11 09:37 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  22. 2026-09-10 09:34 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  23. 2026-09-08 22:00 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  24. 2026-09-07 16:01 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  25. 2026-09-06 13:47 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  26. 2026-09-04 05:06 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  27. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  28. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  29. 2026-08-30 19:17 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  30. 2026-08-30 01:22 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  31. 2026-08-28 21:41 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  32. 2026-08-27 14:25 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  33. 2026-08-26 14:46 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  34. 2026-08-25 13:49 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  35. 2026-08-25 04:19 UTCEG score recompute
  36. 2026-08-23 14:12 UTCEG score recompute
  37. 2026-08-23 00:19 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  38. 2026-08-22 00:36 UTCEG score recompute
  39. 2026-08-21 23:49 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  40. 2026-08-21 02:24 UTCEG score recompute
  41. 2026-08-20 22:55 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  42. 2026-08-20 10:26 UTCEG score recompute
  43. 2026-08-19 17:04 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  44. 2026-08-18 13:48 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  45. 2026-08-17 13:47 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  46. 2026-08-16 15:13 UTCEG score recompute
  47. 2026-08-16 14:56 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  48. 2026-08-16 02:24 UTCEG score recompute
  49. 2026-08-16 02:14 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  50. 2026-08-15 02:35 UTCEG score recompute
  51. 2026-08-15 01:30 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  52. 2026-08-14 00:28 UTCEG score recompute
  53. 2026-08-13 22:00 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  54. 2026-08-12 18:07 UTCEG score recompute
  55. 2026-08-12 13:51 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  56. 2026-08-11 18:27 UTCEG score recompute
  57. 2026-08-11 04:01 UTCEG score recompute
  58. 2026-08-11 00:00 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  59. 2026-08-09 16:38 UTCEG score recompute
  60. 2026-08-09 13:46 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  61. 2026-08-08 19:14 UTCEG score recompute
  62. 2026-08-08 16:37 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  63. 2026-08-07 17:05 UTCEG score recompute
  64. 2026-08-06 14:05 UTCEG score recompute
  65. 2026-08-06 13:46 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  66. 2026-08-05 20:42 UTCEG score recompute
  67. 2026-08-05 19:17 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  68. 2026-08-04 23:09 UTCEG score recompute
  69. 2026-08-04 15:10 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  70. 2026-08-04 10:38 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  71. 2026-08-03 15:56 UTCEG score recompute
  72. 2026-08-03 10:36 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  73. 2026-08-02 02:52 UTCEG score recompute
  74. 2026-08-02 02:27 UTCEPSS rescoreEPSS 0.2% · 12th percentile
  75. 2026-08-01 13:59 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-44649?
CVE-2026-44649 is a critical-severity vulnerability; its CVE record was published on May 29, 2026. SillyTavern is a locally installed user interface that allows users to interact with text generation large language models, image generation engines, and text-to-speech voice models. Prior to 1.18.0, SillyTavern accepts Remote-User (Authelia) and X-Authentik-Username (Authentik) HTTP headers to…
When was the CVE record for CVE-2026-44649 published?
The CVE record for CVE-2026-44649 was published on May 29, 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 July 22, 2026; the record at its source may have been updated since.
Is CVE-2026-44649 actively exploited?
CVE-2026-44649 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.3% probability of exploitation in the next 30 days (20th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2026-44649?
CVE-2026-44649 has a CVSS base score of 9.8 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-44649?
A fix for CVE-2026-44649 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2026-44649 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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