CVE-2023-4039

MEDIUMNVD 4.84.8
EchelonGraph scoreMEDIUM confidence

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

This medium-severity CVE scores 4.8 under NVD CVSS v3. EPSS exploit probability: 1.0% (63rd percentile of EPSS-scored CVEs). No GitHub Security Advisory CVSS is on record for this CVE.

Triggered by: Headline CVSS from NVD CVSS v3
Sources: EPSS, NVD CVSS v3
Elevated
4.8EG
EchelonGraph verdictPlan a fixRemediate within your standard update timelines (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: 1.0%CVSS: 4.8Exploit: No code on recordExposed services: Not assessed

A fix is available — apply it.

DISPUTEDA failure in the -fstack-protector feature in GCC-based toolchains that target AArch64 allows an attacker to exploit an existing buffer overflow in dynamically-sized local variables in your application without this being detected. This stack-protector failure only applies to C99-style dynamically-sized local variables or those created using alloca(). The stack-protector operates as intended for statically-sized local variables.

The default behavior when the stack-protector detects an overflow is to terminate your application, resulting in controlled loss of availability. An attacker who can exploit a buffer overflow without triggering the stack-protector might be able to change program flow control to cause an uncontrolled loss of availability or to go further and affect confidentiality or integrity. NOTE: The GCC project argues that this is a missed hardening bug and not a vulnerability by itself.

CVSS v3
4.8
EG Score
4.8MEDIUMmedium confidence
EG Risk
38
EG Risk 38/100

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)
Severity48% × 45%
Impact severity (EG Severity): CVSS 4.8 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.
Automatability0% × 15%
CISA's SSVC Automatable value: no (Vulnrichment).
SSVC (CISA's decision table, applied by EchelonGraph): Track at low or medium mission impact; Track* at high (mission-essential systems).
Exploitation public PoC (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
1.0%
EPSS %ILE
63rd
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 (4.8): severity, escalated by confirmed exploitation. This CVE's 4.8 is its impact severity (EG Severity), not escalated.

EG Severity
4.8 MEDIUMCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.NVD CVSS v3 · CVSS v3.0 or v3.1
EG Likelihood
1.0% within 30 daysSource: FIRST EPSS (model v2026.06.15, score date 2026-10-17). 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; Track* at high (mission-essential systems).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: the SSVC and BOD 26-04 blocks below.

SSVC (CISA's decision table, applied by EchelonGraph)Track at low or medium mission impact; Track* at high (mission-essential systems).

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

Exploitation public PoC (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.

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

September 13, 2023

Last Modified

October 14, 2026

Advisory Details (2)

Auto-updated Jun 23, 2026
Patch available. Sources: github.
GitHub advisoryMentions a patch (unverified)

GCC's -fstack-protector fails to guard dynamic stack allocations on ARM64 · Advisory · metaredteam/external-disclosures · GitHub

https://github.com/metaredteam/external-disclosures/security/advisories/GHSA-x7ch-h5rf-w2mf

Vendor Advisories for CVE-2023-4039(1)

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

Patch Availability(1)

Vendor / EcosystemFix (by version range) / PatchReleasedSource
ubuntulibx32ubsan1 (12.3.0-1ubuntu1~22.04.2) @ jammy2026-10-14ubuntu

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

(14 across 10 ecosystems)
Debian:11(2)
PackageVulnerable rangeFix by version rangeDependents
gcc-1010.2.1-16 ... 10.5.0-4 (39 versions)
  • every version on: no fix on record
—
gcc-99.3.0-22 ... 9.5.0-6 (16 versions)
  • every version on: no fix on record
—
Debian:12(2)
PackageVulnerable rangeFix by version rangeDependents
gcc-1111.3.0-12 ... 11.5.0-9 (25 versions)
  • every version on: no fix on record
—
gcc-1212.2.0-14
  • every version up to 12.2.0-14+deb12u1: fixed in 12.2.0-14+deb12u1
—
Debian:13(2)
PackageVulnerable rangeFix by version rangeDependents
gcc-12—
  • every version up to 12.3.0-9: fixed in 12.3.0-9
—
gcc-13—
  • every version up to 13.2.0-4: fixed in 13.2.0-4
—
Debian:14(2)
PackageVulnerable rangeFix by version rangeDependents
gcc-12—
  • every version up to 12.3.0-9: fixed in 12.3.0-9
—
gcc-13—
  • every version up to 13.2.0-4: fixed in 13.2.0-4
—
Alpine:v3.19(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—
Alpine:v3.20(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—
Alpine:v3.21(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—
Alpine:v3.22(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—
Alpine:v3.23(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—
Alpine:v3.24(1)
PackageVulnerable rangeFix by version rangeDependents
gcc—
  • every version up to 13.2.1_git20231014-r0: fixed in 13.2.1_git20231014-r0
—

Weakness Classification(1)

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

Additional Vendor Advisories

(1)

Vendors that published advisories for this CVE beyond the curated set above. Broader coverage but minimal per-row detail — click through for the original advisory.

Data Freshness Timeline

(refreshed 8× in last 7d / 34× 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 91 of 202 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. 9 repeat rows among the latest 100 are merged into the row they repeat. The 111 oldest rows on record are not shown and were not checked, so the counts can still include repeats.

  1. 2026-10-23 16:29 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  2. 2026-10-22 16:31 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  3. 2026-10-21 16:29 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  4. 2026-10-20 16:30 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  5. 2026-10-19 16:29 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  6. 2026-10-18 16:29 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  7. 2026-10-18 07:53 UTCEG score recompute
  8. 2026-10-17 16:30 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  9. 2026-10-16 16:36 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  10. 2026-10-15 16:29 UTCEPSS rescoreEPSS 1.0% · 63rd percentile
  11. 2026-10-14 21:35 UTCEG score recompute
  12. 2026-10-14 21:35 UTCVendor advisory
  13. 2026-10-14 16:30 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  14. 2026-10-13 16:30 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  15. 2026-10-12 16:31 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  16. 2026-10-12 16:12 UTCEG score recompute
  17. 2026-10-12 16:12 UTCVendor advisory
  18. 2026-10-11 21:47 UTCEG score recompute
  19. 2026-10-11 13:45 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  20. 2026-10-10 19:57 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  21. 2026-10-09 20:05 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  22. 2026-10-08 17:06 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  23. 2026-10-07 23:46 UTCEPSS rescoreEPSS 0.8% · 54th percentile
  24. 2026-10-06 15:15 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  25. 2026-10-05 17:41 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
Show 66 more
  1. 2026-10-03 14:23 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  2. 2026-10-01 19:48 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  3. 2026-09-30 16:29 UTCEG score recompute
  4. 2026-09-30 15:01 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  5. 2026-09-29 15:17 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  6. 2026-09-28 13:49 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  7. 2026-09-27 13:42 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  8. 2026-09-26 00:22 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  9. 2026-09-24 14:01 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  10. 2026-09-23 13:46 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  11. 2026-09-22 23:32 UTCOSV refresh
  12. 2026-09-22 14:46 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  13. 2026-09-21 20:31 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  14. 2026-09-20 20:14 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  15. 2026-09-18 19:26 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  16. 2026-09-17 19:25 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  17. 2026-09-16 14:06 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  18. 2026-09-16 05:11 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  19. 2026-09-15 03:08 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  20. 2026-09-13 16:44 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  21. 2026-09-12 14:58 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  22. 2026-09-11 14:50 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  23. 2026-09-11 09:34 UTCEPSS rescoreEPSS 0.8% · 53rd percentile
  24. 2026-09-08 21:58 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  25. 2026-09-07 15:59 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  26. 2026-09-06 13:45 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  27. 2026-09-05 15:26 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  28. 2026-09-04 13:58 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  29. 2026-09-04 05:04 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  30. 2026-09-03 18:29 UTCOSV refresh
  31. 2026-09-02 14:09 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  32. 2026-09-01 13:51 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  33. 2026-09-01 04:35 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  34. 2026-08-30 19:15 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  35. 2026-08-30 01:20 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  36. 2026-08-28 21:39 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  37. 2026-08-27 14:23 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  38. 2026-08-26 14:44 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  39. 2026-08-25 13:46 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  40. 2026-08-24 14:14 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  41. 2026-08-23 00:17 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  42. 2026-08-21 23:47 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  43. 2026-08-20 22:53 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  44. 2026-08-19 17:02 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  45. 2026-08-18 13:46 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  46. 2026-08-17 13:45 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  47. 2026-08-17 07:31 UTCOSV refresh
  48. 2026-08-16 14:54 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  49. 2026-08-16 02:12 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  50. 2026-08-15 01:28 UTCEPSS rescoreEPSS 0.8% · 52nd percentile
  51. 2026-08-13 21:58 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  52. 2026-08-12 13:49 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  53. 2026-08-11 13:40 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  54. 2026-08-10 23:57 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  55. 2026-08-09 13:44 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  56. 2026-08-08 16:35 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  57. 2026-08-07 16:25 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  58. 2026-08-06 13:45 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  59. 2026-08-05 19:15 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  60. 2026-08-04 15:07 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  61. 2026-08-04 10:35 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  62. 2026-08-03 10:34 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  63. 2026-08-02 02:25 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  64. 2026-08-02 02:19 UTCOSV refresh
  65. 2026-08-01 04:14 UTCEPSS rescoreEPSS 0.8% · 51st percentile
  66. 2026-07-30 16:26 UTCEPSS rescoreEPSS 0.8% · 51st percentile

Frequently asked(5)

What is CVE-2023-4039?
CVE-2023-4039 is a medium-severity vulnerability; its CVE record was published on September 13, 2023. DISPUTEDA failure in the -fstack-protector feature in GCC-based toolchains that target AArch64 allows an attacker to exploit an existing buffer overflow in dynamically-sized local variables in your application without this being detected. This stack-protector failure only applies to C99-style…
When was CVE-2023-4039 made public?
CVE-2023-4039 was made public on September 12, 2023: that is the date its CVE record's CNA, Arm Limited, gives for when the vulnerability was made public. The CVE record itself was published on September 13, 2023. EchelonGraph's copy of the record carries a last-modified date of October 14, 2026; the record at its source may have been updated since.
Is CVE-2023-4039 actively exploited?
CVE-2023-4039 is not currently on CISA's Known Exploited Vulnerabilities catalog. FIRST EPSS estimates a 1.0% probability of exploitation in the next 30 days (63rd percentile of EPSS-scored CVEs).
What is the CVSS score of CVE-2023-4039?
CVE-2023-4039 has a CVSS v3 base score of 4.8 (NVD).
How do I remediate CVE-2023-4039?
A fix for CVE-2023-4039 is available: update to the fixed version the vendor names in its advisory. The vendor advisories EchelonGraph has for CVE-2023-4039 are linked in the Vendor Advisories panel on this page.

Dependency Blast Radius

See which npm, PyPI, Go, and Maven packages are affected by CVE-2023-4039

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