CVE-2023-1523

CRITICALNVD 10.010.0
EchelonGraph scoreMEDIUM confidence

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

Score 10.0 from GitHub Security Advisory (severity: CRITICAL) published 2023-09-01. NVD baseline CVSS 10.0; sources differ by 0.0.

Triggered by: GitHub Security Advisory CVSS
Sources: EPSS, GitHub Security Advisory, NVD CVSS v3
Elevated

Also known asEUVD-2023-23767 (ENISA EUVD) · GHSA-55wx-23fj-c2v5 (GitHub Security Advisories)Source: ENISA EUVD

10.0EG
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: 1.4%CVSS: 10.0Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

Using the TIOCLINUX ioctl request, a malicious snap could inject contents into the input of the controlling terminal which could allow it to cause arbitrary commands to be executed outside of the snap sandbox after the snap exits. Graphical terminal emulators like xterm, gnome-terminal and others are not affected - this can only be exploited when snaps are run on a virtual console.

CVSS v3
10.0
EG Score
10.0CRITICALmedium confidence
EG Risk
76
EG Risk 76/100

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)
Severity100% × 45%
Impact severity (EG Severity): CVSS 10.0 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
1.4%
EPSS %ILE
73rd
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 (10.0): severity, escalated by confirmed exploitation. This CVE's 10.0 is its impact severity (EG Severity), not escalated.

EG Severity
10.0 CRITICALCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
EG Likelihood
1.4% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-11-12). 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, 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, 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.

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

September 1, 2023

Last Modified

November 21, 2024

Advisory Details (4)

Auto-updated Nov 8, 2026
Patch available. Sources: github_pr, ubuntu.
UbuntuMentions a patch (unverified)

USN-6125-1: snapd vulnerability | Ubuntu security notices | Ubuntu

https://ubuntu.com/security/notices/USN-6125-1
Web page

'Re: [oss-security] TTY pushback vulnerabilities / TIOCSTI' - MARC

https://marc.info/?l=oss-security&m=167879021709955&w=2
GitHub pull request Patch Available

many: introduce seccomp denylist to block ioctl with TIOCLINUX to fix CVE-2023-1523

Patch available: snapcore/snapd 2.61.3 (PR #12849 merged 2023-05-26)

https://github.com/snapcore/snapd/pull/12849
Web page
https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-1523

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntuubuntu-snappy (2.54.3+16.04.0ubuntu0.1~esm6) @ xenial2026-11-12ubuntu

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

(4 across 4 ecosystems)
Debian:11(1)
PackageVulnerable rangeFix by version rangeDependents
snapd2.49-1 ... 2.76-1 (40 versions)
  • every version on: no fix on record
—
Debian:12(1)
PackageVulnerable rangeFix by version rangeDependents
snapd2.57.6-1 ... 2.77.1-2 (37 versions)
  • every version on: no fix on record
—
Debian:13(1)
PackageVulnerable rangeFix by version rangeDependents
snapd—
  • every version up to 2.59.5-1: fixed in 2.59.5-1
—
Debian:14(1)
PackageVulnerable rangeFix by version rangeDependents
snapd—
  • every version up to 2.59.5-1: fixed in 2.59.5-1
—

Weakness Classification(1)

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

All Vendor Advisories

(1)

Every vendor that published an advisory referencing this CVE — pulled from our cve_vendor_advisories aggregation. Click any row for the vendor's original advisory page.

Data Freshness Timeline

(refreshed 15× in last 7d / 76× 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.

Showing the most recent 100 of 302 rows 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 202 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-11-13 04:20 UTCEchelonGraph re-scored
  2. 2026-11-13 04:20 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  3. 2026-11-12 16:30 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  4. 2026-11-12 04:21 UTCEchelonGraph re-scored
  5. 2026-11-12 04:21 UTCVendor advisory
  6. 2026-11-12 04:21 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  7. 2026-11-11 16:33 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  8. 2026-11-11 04:21 UTCEchelonGraph re-scored
  9. 2026-11-11 04:21 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  10. 2026-11-10 16:36 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  11. 2026-11-10 04:20 UTCEchelonGraph re-scored
  12. 2026-11-10 04:20 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  13. 2026-11-09 16:30 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  14. 2026-11-09 04:23 UTCEchelonGraph re-scored
  15. 2026-11-09 04:23 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  16. 2026-11-08 16:34 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  17. 2026-11-08 04:25 UTCEchelonGraph re-scored
  18. 2026-11-08 04:25 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  19. 2026-11-07 16:34 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  20. 2026-11-07 04:27 UTCEchelonGraph re-scored
  21. 2026-11-07 04:27 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  22. 2026-11-06 16:31 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  23. 2026-11-06 04:33 UTCEchelonGraph re-scored
  24. 2026-11-06 04:33 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  25. 2026-11-05 16:32 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
Show 75 more
  1. 2026-11-05 04:41 UTCEchelonGraph re-scored
  2. 2026-11-05 04:41 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  3. 2026-11-04 16:31 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  4. 2026-11-04 09:55 UTCOSV refresh
  5. 2026-11-04 04:48 UTCEchelonGraph re-scored
  6. 2026-11-04 04:48 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  7. 2026-11-03 16:40 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  8. 2026-11-03 04:55 UTCEchelonGraph re-scored
  9. 2026-11-03 04:55 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  10. 2026-11-02 16:39 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  11. 2026-11-02 05:02 UTCEchelonGraph re-scored
  12. 2026-11-02 05:02 UTCVendor advisory
  13. 2026-11-02 05:01 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  14. 2026-11-01 16:30 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  15. 2026-11-01 05:09 UTCEchelonGraph re-scored
  16. 2026-11-01 05:09 UTCVendor advisory
  17. 2026-11-01 05:09 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  18. 2026-10-31 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  19. 2026-10-31 05:17 UTCEchelonGraph re-scored
  20. 2026-10-31 05:16 UTCVendor advisory
  21. 2026-10-31 05:16 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  22. 2026-10-30 16:31 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  23. 2026-10-30 05:23 UTCEchelonGraph re-scored
  24. 2026-10-30 05:23 UTCVendor advisory
  25. 2026-10-30 05:23 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  26. 2026-10-29 16:30 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  27. 2026-10-29 05:30 UTCEchelonGraph re-scored
  28. 2026-10-29 05:30 UTCVendor advisory
  29. 2026-10-29 05:30 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  30. 2026-10-28 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  31. 2026-10-28 05:37 UTCEchelonGraph re-scored
  32. 2026-10-28 05:37 UTCVendor advisory
  33. 2026-10-28 05:37 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  34. 2026-10-27 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  35. 2026-10-27 05:45 UTCEchelonGraph re-scored
  36. 2026-10-27 05:45 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  37. 2026-10-26 16:28 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  38. 2026-10-26 01:49 UTCVendor advisory
  39. 2026-10-26 01:49 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  40. 2026-10-25 17:52 UTCEchelonGraph re-scored
  41. 2026-10-25 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  42. 2026-10-25 01:56 UTCEchelonGraph re-scored
  43. 2026-10-25 01:56 UTCVendor advisory
  44. 2026-10-25 01:56 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  45. 2026-10-24 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  46. 2026-10-24 02:03 UTCEchelonGraph re-scored
  47. 2026-10-24 02:03 UTCVendor advisory
  48. 2026-10-24 02:03 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  49. 2026-10-23 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  50. 2026-10-23 02:10 UTCEchelonGraph re-scored
  51. 2026-10-23 02:10 UTCVendor advisory
  52. 2026-10-23 02:09 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  53. 2026-10-22 16:30 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  54. 2026-10-22 02:15 UTCEchelonGraph re-scored
  55. 2026-10-22 02:15 UTCVendor advisory
  56. 2026-10-22 02:15 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  57. 2026-10-21 16:29 UTCEPSS rescoreEPSS 1.4% · 73rd percentile
  58. 2026-10-21 02:19 UTCEchelonGraph re-scored
  59. 2026-10-21 02:19 UTCVendor advisory
  60. 2026-10-21 02:19 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  61. 2026-10-20 16:29 UTCEPSS rescoreEPSS 1.4% · 72nd percentile
  62. 2026-10-20 02:24 UTCEchelonGraph re-scored
  63. 2026-10-20 02:24 UTCVendor advisory
  64. 2026-10-20 02:24 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  65. 2026-10-19 16:29 UTCEPSS rescoreEPSS 1.4% · 72nd percentile
  66. 2026-10-19 01:46 UTCEchelonGraph re-scored
  67. 2026-10-19 01:45 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  68. 2026-10-18 16:29 UTCEPSS rescoreEPSS 1.4% · 72nd percentile
  69. 2026-10-18 08:16 UTCEchelonGraph re-scored
  70. 2026-10-18 01:50 UTCEchelonGraph re-scored
  71. 2026-10-18 01:50 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  72. 2026-10-17 16:29 UTCEPSS rescoreEPSS 1.4% · 72nd percentile
  73. 2026-10-17 01:56 UTCEchelonGraph re-scored
  74. 2026-10-17 01:56 UTCGHSA enrichmentGHSA-55wx-23fj-c2v5 · GitHub severity CRITICAL · GitHub CVSS 10.0
  75. 2026-10-16 16:35 UTCEPSS rescoreEPSS 1.4% · 72nd percentile

Related CVEs(same product + same CWE)

Frequently asked(5)

What is CVE-2023-1523?
CVE-2023-1523 is a critical-severity vulnerability; its CVE record was published on September 1, 2023. Using the TIOCLINUX ioctl request, a malicious snap could inject contents into the input of the controlling terminal which could allow it to cause arbitrary commands to be executed outside of the snap sandbox after the snap exits. Graphical terminal emulators like xterm, gnome-terminal and others…
When was CVE-2023-1523 made public?
CVE-2023-1523 was made public on May 25, 2023: that is the date its CVE record's CNA, Canonical Ltd., gives for when the vulnerability was made public. The CVE record itself was published on September 1, 2023. 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-2023-1523 actively exploited?
CVE-2023-1523 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.4% probability of exploitation in the next 30 days (73rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-1523?
CVE-2023-1523 has a CVSS v3 base score of 10.0 (NVD).
How do I remediate CVE-2023-1523?
A fix for CVE-2023-1523 is available: update to the fixed version the vendor names in its advisory.

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