CVE-2026-77956

HIGHPre-NVD 8.98.9
EchelonGraph scoreMEDIUM confidence

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

This high-severity CVE scores 8.9 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

Also known asEUVD-2026-68303 (ENISA EUVD)Source: ENISA EUVD

8.9EG
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: 8.9Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Improper Control of Generation of Code (Code Injection) vulnerability in ash-project ash_ai allows a remote, unauthenticated client to execute arbitrary Elixir code.

AshAi.Actions.Prompt evaluates prompt content through EEx.eval_string/2. The documented prompt: fn input, context -> ... end form lets the prompt content be built from action arguments, so when a prompt action's text incorporates request data, that attacker-controlled text is compiled and run as an EEx template (Elixir source). Content such as <%= System.cmd(...) %> therefore executes on the server before any model request is made, requiring no authentication beyond reaching a prompt action. The fix stops evaluating function-supplied prompt content as EEx; only statically configured templates are evaluated.

This issue affects ash_ai: from 0.1.0 before 1.0.0.

CVSS v3
8.9
EG Score
8.9HIGHmedium confidence
EG Risk
56
EG Risk 56/100

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)
Severity89% × 45%
Impact severity (EG Severity): CVSS 8.9 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.
Automatability0% × 15%
CISA's SSVC Automatable value: no (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 no (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 (8.9): severity, escalated by confirmed exploitation. This CVE's 8.9 is its impact severity (EG Severity), not escalated.

EG Severity
8.9 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
0.3% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-24). 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: 14 days if the affected system is publicly exposed; Fix on system upgrade 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 no (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)14 days if the affected system is publicly exposed; Fix on system upgrade if it is not.

In CISA KEV no (CISA's KEV catalog) · Automatable no (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

August 31, 2026

Last Modified

September 1, 2026

Advisory Details (4)

Auto-updated Aug 31, 2026
Patch available. Sources: github, github_commit.
Web page

OSV - Open Source Vulnerabilities

https://osv.dev/vulnerability/EEF-CVE-2026-77956
GitHub advisoryMentions a patch (unverified)

Remote code execution in `AshAi.Actions.Prompt` in AshAi via EEx evaluation of prompt content built from user input · Advisory · ash-project/ash_ai · GitHub

https://github.com/ash-project/ash_ai/security/advisories/GHSA-2g59-hg7m-qc83
GitHub commit Patch Available

commit e9948254b565 (ash-project/ash_ai)

Patch available: ash-project/ash_ai v1.0.0 (contains commit e9948254b565)

https://github.com/ash-project/ash_ai/commit/e9948254b5659c1143b73dc2f59f457931e64514

Affected Packages

(1 across 1 ecosystem)
Hex(1)
PackageVulnerable rangeFix by version rangeDependents
ash_ai0.1.0 ... 0.8.2 (38 versions)
  • 0.1.0 up to 1.0.0: fixed in 1.0.0
—

Weakness Classification(1)

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

Data Freshness Timeline

(refreshed 9× in last 7d / 50× 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 97 of 103 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. 3 repeat rows among the latest 100 are merged into the row they repeat. The 6 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-26 16:32 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  2. 2026-10-25 16:34 UTCEPSS rescoreEPSS 0.3% · 20th percentile
  3. 2026-10-25 14:01 UTCEG score recompute
  4. 2026-10-24 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  5. 2026-10-23 16:32 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  6. 2026-10-22 16:35 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  7. 2026-10-21 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  8. 2026-10-20 18:20 UTCEG score recompute
  9. 2026-10-20 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  10. 2026-10-19 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  11. 2026-10-18 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  12. 2026-10-18 03:11 UTCEG score recompute
  13. 2026-10-17 16:35 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  14. 2026-10-16 16:44 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  15. 2026-10-15 16:32 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  16. 2026-10-14 16:33 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  17. 2026-10-13 16:35 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  18. 2026-10-13 06:52 UTCEG score recompute
  19. 2026-10-12 16:35 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  20. 2026-10-12 15:37 UTCEG score recompute
  21. 2026-10-11 19:23 UTCEG score recompute
  22. 2026-10-11 16:39 UTCEG score recompute
  23. 2026-10-11 13:57 UTCEG score recompute
  24. 2026-10-11 13:49 UTCEPSS rescoreEPSS 0.3% · 19th percentile
  25. 2026-10-10 20:00 UTCEPSS rescoreEPSS 0.3% · 19th percentile
Show 72 more
  1. 2026-10-10 00:39 UTCEG score recompute
  2. 2026-10-09 20:07 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  3. 2026-10-09 02:27 UTCEG score recompute
  4. 2026-10-08 17:13 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  5. 2026-10-08 00:38 UTCEG score recompute
  6. 2026-10-07 23:48 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  7. 2026-10-06 19:12 UTCEG score recompute
  8. 2026-10-06 15:18 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  9. 2026-10-05 19:03 UTCEG score recompute
  10. 2026-10-05 17:43 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  11. 2026-10-05 07:19 UTCEG score recompute
  12. 2026-10-04 23:22 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  13. 2026-10-03 19:18 UTCEG score recompute
  14. 2026-10-03 14:26 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  15. 2026-10-02 19:17 UTCEG score recompute
  16. 2026-10-02 07:29 UTCEG score recompute
  17. 2026-10-01 19:50 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  18. 2026-09-30 19:46 UTCEG score recompute
  19. 2026-09-30 03:45 UTCEG score recompute
  20. 2026-09-29 15:24 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  21. 2026-09-29 08:48 UTCEG score recompute
  22. 2026-09-28 21:04 UTCEG score recompute
  23. 2026-09-28 13:52 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  24. 2026-09-27 18:47 UTCEG score recompute
  25. 2026-09-27 13:48 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  26. 2026-09-26 19:18 UTCEG score recompute
  27. 2026-09-26 15:59 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  28. 2026-09-26 07:18 UTCEG score recompute
  29. 2026-09-26 00:28 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  30. 2026-09-24 19:20 UTCEG score recompute
  31. 2026-09-24 14:04 UTCEPSS rescoreEPSS 0.3% · 18th percentile
  32. 2026-09-23 19:51 UTCEG score recompute
  33. 2026-09-23 17:54 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  34. 2026-09-22 19:21 UTCEG score recompute
  35. 2026-09-22 16:01 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  36. 2026-09-22 07:36 UTCEG score recompute
  37. 2026-09-21 21:09 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  38. 2026-09-20 20:24 UTCEG score recompute
  39. 2026-09-20 20:16 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  40. 2026-09-19 20:55 UTCEG score recompute
  41. 2026-09-18 21:26 UTCEG score recompute
  42. 2026-09-18 19:28 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  43. 2026-09-17 20:57 UTCEG score recompute
  44. 2026-09-16 21:29 UTCEG score recompute
  45. 2026-09-16 14:08 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  46. 2026-09-16 09:11 UTCEG score recompute
  47. 2026-09-16 05:15 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  48. 2026-09-15 09:42 UTCEG score recompute
  49. 2026-09-15 03:12 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  50. 2026-09-13 22:29 UTCEG score recompute
  51. 2026-09-12 23:01 UTCEG score recompute
  52. 2026-09-11 23:32 UTCEG score recompute
  53. 2026-09-11 14:53 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  54. 2026-09-11 11:47 UTCEG score recompute
  55. 2026-09-10 11:42 UTCEG score recompute
  56. 2026-09-10 09:35 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  57. 2026-09-08 23:33 UTCEG score recompute
  58. 2026-09-08 22:01 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  59. 2026-09-07 18:24 UTCEG score recompute
  60. 2026-09-06 18:54 UTCEG score recompute
  61. 2026-09-06 13:48 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  62. 2026-09-05 19:24 UTCEG score recompute
  63. 2026-09-04 19:55 UTCEG score recompute
  64. 2026-09-04 08:07 UTCEG score recompute
  65. 2026-09-04 05:07 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  66. 2026-09-02 20:53 UTCEG score recompute
  67. 2026-09-02 14:12 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  68. 2026-09-01 16:07 UTCEG score recompute
  69. 2026-09-01 13:54 UTCEPSS rescoreEPSS 0.2% · 9th percentile
  70. 2026-09-01 04:40 UTCEPSS rescoreEPSS 0.4% · 30th percentile
  71. 2026-09-01 04:14 UTCEG score recompute
  72. 2026-08-31 16:25 UTCEG score recompute

Frequently asked(5)

What is CVE-2026-77956?
CVE-2026-77956 is a high-severity vulnerability; its CVE record was published on August 31, 2026. Improper Control of Generation of Code (Code Injection) vulnerability in ash-project ash_ai allows a remote, unauthenticated client to execute arbitrary Elixir code. AshAi.Actions.Prompt evaluates prompt content through EEx.eval_string/2. The documented prompt: fn input, context -> ... end form…
When was the CVE record for CVE-2026-77956 published?
The CVE record for CVE-2026-77956 was published on August 31, 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 September 1, 2026; the record at its source may have been updated since.
Is CVE-2026-77956 actively exploited?
CVE-2026-77956 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-2026-77956?
CVE-2026-77956 has a CVSS base score of 8.9 (a secondary CVSS source that NVD displays; NVD's own analysis pending).
How do I remediate CVE-2026-77956?
A fix for CVE-2026-77956 is available: update to the fixed version the vendor names in its advisory.

Dependency Blast Radius

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