FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to 3.24.0, a size_t underflow in the IMA-ADPCM and MS-ADPCM audio decoders leads to heap-buffer-overflow write via the RDPSND audio channel. In libfreerdp/codec/dsp.c, the IMA-ADPCM and MS-ADPCM decoders subtract block header sizes from a size_t variable without checking for underflow. When nBlockAlign (received from the server) is set such that size % block_size == 0 triggers the header parsing at a point where size is smaller than the header (4 or 8 bytes), the subtraction wraps size to ~SIZE_MAX. The while (size > 0) loop then continues for an astronomical number of iterations. This vulnerability is fixed in 3.24.0.
CVE-2026-31883
This medium-severity CVE scores 6.5 under the CNA's CVSS (NVD's own analysis pending). EPSS exploit-prediction score not yet available (the EPSS model rescores nightly; freshly-published CVEs typically appear within 48 hours). GitHub Security Advisory data not yet ingested — confidence will rise once GHSA publishes (typical lag: hours to days for open-source ecosystem CVEs; never for infrastructure-only CVEs).
- High severity, but no confirmed exploitation yet
A fix is available — apply it.
- CVSS v3
- 9.8
- EG Score
- 6.5(low)
- EG Risk
- 60(Attend)EG Risk 60/100SSVC: Attend
EG Risk is EchelonGraph's 0–100 priority score: it fuses intrinsic severity with real-world exploitation and automatability so you can rank equal-severity CVEs and fix the most dangerous first. Higher = act sooner. Distinct from the 0–10 EG Score (severity).
How it’s computedSeverity65% × 45%Exploitation40% × 40%Automatability100% × 15%Action: Remediate soon — notable exploitation risk. - EPSS PROB
- 0%
- EPSS %ILE
- 24%
- KEV
- Not listed
Published
March 13, 2026
Last Modified
June 17, 2026
Advisory Details (2)
Auto-updated Jul 27, 2026`size_t` underflow in ADPCM decoder leads to heap-buffer-overflow write · Advisory · FreeRDP/FreeRDP · GitHub
https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-85x9-4xxp-xhm5commit 16df2300e1e3 (FreeRDP/FreeRDP)
Fix landed in FreeRDP/FreeRDP commit 16df2300e1e3 — awaiting tagged release
https://github.com/FreeRDP/FreeRDP/commit/16df2300e1e3f5a51f68fb1626429e58b531b7c8Vendor Advisories for CVE-2026-31883(14)
These vendors published their own advisory mentioning this CVE — often with vendor-specific remediation steps + affected product lists not in NVD.
- RHSA-2026:20605Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:20546Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:19811Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:19358Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:19142Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:16865Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:16866Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- RHSA-2026:16814Red Hat Product SecurityMedium
Red Hat Security Advisory: freerdp security update
- +6 more
Patch Availability(14)
| Vendor / Ecosystem | Fixed in / Patch | Released | Source |
|---|---|---|---|
| redhat | freerdp-2:3.10.3-3.el10_0.7 | 2026-05-26 | redhat |
| redhat | freerdp-0:2.1.1-5.el7_9.9 | 2026-05-26 | redhat |
| redhat | freerdp-2:2.2.0-14.el8_4 | 2026-05-20 | redhat |
| redhat | freerdp-2:3.10.3-12.el10_2.5 | 2026-05-19 | redhat |
| redhat | freerdp-2:2.11.7-7.el9_8.3 | 2026-05-19 | redhat |
| redhat | freerdp-2:2.11.7-1.el9_6.10 | 2026-05-13 | redhat |
| redhat | freerdp-2:2.2.0-7.el8_6.8 | 2026-05-13 | redhat |
| redhat | freerdp-2:2.2.0-12.el8_8.8 | 2026-05-13 | redhat |
| redhat | freerdp-2:2.11.7-1.el9_7.7 | 2026-05-13 | redhat |
| redhat | freerdp-2:2.11.2-1.el9_4.8 | 2026-05-13 | redhat |
| redhat | freerdp-2:2.4.1-3.el9_0.7 | 2026-05-12 | redhat |
| redhat | freerdp-2:2.4.1-6.el9_2.9 | 2026-05-12 | redhat |
| redhat | freerdp-2:2.11.7-9.el8_10 | 2026-05-11 | redhat |
| redhat | freerdp-2:3.10.3-5.el10_1.8 | 2026-05-11 | redhat |
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.
Weakness Classification(2)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 3× in last 7d / 3× in last 30d)
Each row is a source pipeline that fetched or updated this CVE on that date, with what changed. 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. Most recent first.
- 2026-07-27 12:52 UTCEG score recompute
- 2026-07-27 12:52 UTCVendor advisory
- 2026-07-27 12:50 UTCOSV refresh
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