FreeRDP is a free implementation of the Remote Desktop Protocol. Prior to version 3.24.2, a malicious RDP server can crash the FreeRDP client by sending audio data in IMA ADPCM format with an invalid initial step index value (>= 89). The unvalidated step index is read directly from the network and used to index into a 89-entry lookup table, triggering a WINPR_ASSERT() failure and process abort via SIGABRT. This affects any FreeRDP client that has audio redirection (RDPSND) enabled, which is the default configuration. This issue has been patched in version 3.24.2.
CVE-2026-33977
This medium-severity CVE scores 6.5 under NVD CVSS v3. 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).
- Lower severity and no public exploit yet
No vendor fix yet — apply a workaround or compensating control (WAF / firewall / segmentation) and watch for a patch.
- CVSS v3
- 6.5
- EG Score
- 6.5(low)
- EG Risk
- 34(Track)EG Risk 34/100SSVC: Track
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%Exploitation0% × 40%Automatability30% × 15%Action: Routine — remediate on your standard cadence. - EPSS PROB
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- EPSS %ILE
- —
- KEV
- Not listed
Published
March 30, 2026
Last Modified
June 17, 2026
References (3)
- security-advisories@githubhttps://github.com/FreeRDP/FreeRDP/commit/9be3f03d94a50892fd58a9f7dee72b2313c69b47
- security-advisories@githubhttps://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8f2g-3q27-6xm5
- 134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/FreeRDP/FreeRDP/security/advisories/GHSA-8f2g-3q27-6xm5
Weakness Classification(1)
MITRE Common Weakness Enumeration — the root-cause categories this CVE belongs to.
Data Freshness Timeline
(refreshed 1× in last 7d / 1× 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 14:17 UTCEG score recompute
Related CVEs(same CWE)
Same CWE
10 shownCWE-617
- CVE-2006-5779NVD 7.5EG 8.7EPSS p99HIGH
- CVE-2018-5740NVD 7.5EG 8.3EPSS p99HIGH
- CVE-2018-19963EG 7.8HIGH
- CVE-2017-7605EG 7.8HIGH
- CVE-2018-12543NVD 7.5EG 7.7EPSS p98HIGH
- CVE-2016-8864NVD 7.5EG 7.7EPSS p98HIGH
- CVE-2019-14022EG 7.5HIGH
- CVE-2015-8012EG 7.5HIGH
- CVE-2011-3596EG 7.5EPSS p95HIGH
- CVE-2018-5742EG 7.5HIGH
Frequently asked(4)
What is CVE-2026-33977?
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Dependency Blast Radius
Explore the affected products and dependency analysis for CVE-2026-33977
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