CVE-2023-40359

CRITICALNVD 9.89.8
EchelonGraph scoreMEDIUM confidence

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

Score 9.8 from GitHub Security Advisory (severity: CRITICAL) published 2023-08-14. NVD baseline CVSS 9.8; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Trending — 4 sources updated this week

Also known asEUVD-2023-44930 (ENISA EUVD) · GHSA-cwvr-vg72-6p6j (GitHub Security Advisories)Source: ENISA EUVD

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).
  • High severity, but no confirmed exploitation yet
CISA-KEV: Not listedEPSS PROB: 0.9%CVSS: 9.8Exploit: None knownExposed services: Not assessed

A fix is available — apply it.

xterm before 380 supports ReGIS reporting for character-set names even if they have unexpected characters (i.e., neither alphanumeric nor underscore), aka a pointer/overflow issue. This can only occur for xterm installations that are configured at compile time to use a certain experimental feature.

CVSS v3
9.8
EG Score
9.8CRITICALmedium confidence
EG Risk
59
EG Risk 59/100

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.
Exploitation0.9% × 40%
FIRST EPSS: the 30-day exploitation probability when EchelonGraph scored this CVE.
Automatability100% × 15%
CISA's SSVC Automatable value: yes (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Attend at high (mission-essential systems).
Exploitation none (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
0.9%
EPSS %ILE
58th
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.GitHub Security Advisory CVSS
EG Likelihood
0.9% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-01). 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; Attend at high (mission-essential systems).CISA BOD 26-04: 3 days if the affected system is publicly exposed; 60 days 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; Attend at high (mission-essential systems).

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

Exploitation none (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.

The score's inputs: 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

August 14, 2023

Last Modified

November 21, 2024

Advisory Details (1)

Auto-updated Oct 10, 2026
Patch available.

Affected Packages

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
xterm366-1 ... 410-1 (48 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
xterm379-1 ... 411-1 (32 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
xterm—
  • every version up to 382-2: fixed in 382-2
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
xterm—
  • every version up to 382-2: fixed in 382-2
—

Data Freshness Timeline

(refreshed 25× in last 7d / 82× 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 95 of 270 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. 5 repeat rows among the latest 100 are merged into the row they repeat. The 175 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-01 20:27 UTCEG score recompute
  2. 2026-11-01 20:27 UTCVendor advisory
  3. 2026-11-01 20:27 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  4. 2026-11-01 16:31 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  5. 2026-10-31 18:08 UTCEG score recompute
  6. 2026-10-31 18:08 UTCVendor advisory
  7. 2026-10-31 18:08 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-10-31 16:30 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  9. 2026-10-30 16:31 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  10. 2026-10-30 15:48 UTCEG score recompute
  11. 2026-10-30 15:48 UTCVendor advisory
  12. 2026-10-30 15:48 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  13. 2026-10-29 16:30 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  14. 2026-10-29 13:29 UTCEG score recompute
  15. 2026-10-29 13:29 UTCVendor advisory
  16. 2026-10-29 13:28 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  17. 2026-10-28 16:29 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  18. 2026-10-28 11:09 UTCEG score recompute
  19. 2026-10-28 11:09 UTCVendor advisory
  20. 2026-10-28 11:09 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  21. 2026-10-27 16:29 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  22. 2026-10-27 08:08 UTCEG score recompute
  23. 2026-10-27 08:08 UTCVendor advisory
  24. 2026-10-27 08:08 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  25. 2026-10-26 16:28 UTCEPSS rescoreEPSS 0.9% · 58th percentile
Show 70 more
  1. 2026-10-26 03:33 UTCVendor advisory
  2. 2026-10-26 03:33 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  3. 2026-10-25 17:37 UTCEG score recompute
  4. 2026-10-25 16:29 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  5. 2026-10-25 01:09 UTCEG score recompute
  6. 2026-10-25 01:09 UTCVendor advisory
  7. 2026-10-25 01:09 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  8. 2026-10-24 16:29 UTCEPSS rescoreEPSS 0.9% · 58th percentile
  9. 2026-10-23 22:50 UTCEG score recompute
  10. 2026-10-23 22:50 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  11. 2026-10-23 16:29 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  12. 2026-10-22 20:16 UTCEG score recompute
  13. 2026-10-22 20:16 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  14. 2026-10-22 16:31 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  15. 2026-10-21 17:54 UTCEG score recompute
  16. 2026-10-21 17:54 UTCVendor advisory
  17. 2026-10-21 17:54 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  18. 2026-10-21 16:29 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  19. 2026-10-20 16:30 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  20. 2026-10-20 15:35 UTCEG score recompute
  21. 2026-10-20 15:35 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  22. 2026-10-19 16:29 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  23. 2026-10-19 13:16 UTCEG score recompute
  24. 2026-10-19 13:16 UTCVendor advisory
  25. 2026-10-19 13:16 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  26. 2026-10-18 16:29 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  27. 2026-10-18 10:57 UTCVendor advisory
  28. 2026-10-18 10:57 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  29. 2026-10-18 07:53 UTCEG score recompute
  30. 2026-10-17 16:30 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  31. 2026-10-17 05:41 UTCEG score recompute
  32. 2026-10-17 05:41 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  33. 2026-10-16 16:36 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  34. 2026-10-16 03:21 UTCEG score recompute
  35. 2026-10-16 03:21 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  36. 2026-10-15 16:29 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  37. 2026-10-15 00:03 UTCEG score recompute
  38. 2026-10-15 00:02 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  39. 2026-10-14 16:30 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  40. 2026-10-13 19:12 UTCEG score recompute
  41. 2026-10-13 19:12 UTCVendor advisory
  42. 2026-10-13 19:12 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  43. 2026-10-13 16:30 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  44. 2026-10-12 16:50 UTCEG score recompute
  45. 2026-10-12 16:50 UTCVendor advisory
  46. 2026-10-12 16:50 UTCGHSA enrichmentGHSA-cwvr-vg72-6p6j · GitHub severity CRITICAL · GitHub CVSS 9.8
  47. 2026-10-12 16:31 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  48. 2026-10-11 21:47 UTCEG score recompute
  49. 2026-10-11 13:45 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  50. 2026-10-10 19:57 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  51. 2026-10-09 20:05 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  52. 2026-10-08 17:06 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  53. 2026-10-07 23:46 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  54. 2026-10-06 15:15 UTCEPSS rescoreEPSS 0.9% · 57th percentile
  55. 2026-10-05 17:41 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  56. 2026-10-04 23:20 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  57. 2026-10-03 14:23 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  58. 2026-10-01 19:48 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  59. 2026-09-30 16:29 UTCEG score recompute
  60. 2026-09-30 15:01 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  61. 2026-09-29 15:17 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  62. 2026-09-28 13:49 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  63. 2026-09-27 13:42 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  64. 2026-09-26 15:56 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  65. 2026-09-26 00:22 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  66. 2026-09-24 14:01 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  67. 2026-09-23 13:46 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  68. 2026-09-23 02:32 UTCOSV refresh
  69. 2026-09-20 20:14 UTCEPSS rescoreEPSS 0.9% · 56th percentile
  70. 2026-09-18 19:25 UTCEPSS rescoreEPSS 0.9% · 56th percentile

Frequently asked(5)

What is CVE-2023-40359?
CVE-2023-40359 is a critical-severity vulnerability; its CVE record was published on August 14, 2023. xterm before 380 supports ReGIS reporting for character-set names even if they have unexpected characters (i.e., neither alphanumeric nor underscore), aka a pointer/overflow issue. This can only occur for xterm installations that are configured at compile time to use a certain experimental feature.
When was the CVE record for CVE-2023-40359 published?
The CVE record for CVE-2023-40359 was published on August 14, 2023. 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 November 21, 2024; the record at its source may have been updated since.
Is CVE-2023-40359 actively exploited?
CVE-2023-40359 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 0.9% probability of exploitation in the next 30 days (58th percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-40359?
CVE-2023-40359 has a CVSS v3 base score of 9.8 (NVD).
How do I remediate CVE-2023-40359?
A fix for CVE-2023-40359 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2023-40359 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

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