In the Linux kernel, the following vulnerability has been resolved:
drm/amdgpu: Fix buffer size in gfx_v9_4_3_init_ cp_compute_microcode() and rlc_microcode()
The function gfx_v9_4_3_init_microcode in gfx_v9_4_3.c was generating
about potential truncation of output when using the snprintf function.
The issue was due to the size of the buffer 'ucode_prefix' being too
small to accommodate the maximum possible length of the string being
written into it.
The string being written is "amdgpu/%s_mec.bin" or "amdgpu/%s_rlc.bin",
where %s is replaced by the value of 'chip_name'. The length of this
string without the %s is 16 characters. The warning message indicated
that 'chip_name' could be up to 29 characters long, resulting in a total
of 45 characters, which exceeds the buffer size of 30 characters.
To resolve this issue, the size of the 'ucode_prefix' buffer has been
reduced from 30 to 15. This ensures that the maximum possible length of
the string being written into the buffer will not exceed its size, thus
preventing potential buffer overflow and truncation issues.
Fixes the below with gcc W=1:
drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c: In function ‘gfx_v9_4_3_early_init’:
drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:379:52: warning: ‘%s’ directive output may be truncated writing up to 29 bytes into a region of size 23 [-Wformat-truncation=]
379 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", chip_name);
| ^~
......
439 | r = gfx_v9_4_3_init_rlc_microcode(adev, ucode_prefix);
| ~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:379:9: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 30
379 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_rlc.bin", chip_name);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:413:52: warning: ‘%s’ directive output may be truncated writing up to 29 bytes into a region of size 23 [-Wformat-truncation=]
413 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec.bin", chip_name);
| ^~
......
443 | r = gfx_v9_4_3_init_cp_compute_microcode(adev, ucode_prefix);
| ~~~~~~~~~~~~
drivers/gpu/drm/amd/amdgpu/gfx_v9_4_3.c:413:9: note: ‘snprintf’ output between 16 and 45 bytes into a destination of size 30
413 | snprintf(fw_name, sizeof(fw_name), "amdgpu/%s_mec.bin", chip_name);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
What the EG score is made of (scorer v4.0: the three questions the 0–10 score mixes, published apart · methodology)
The EG score (7.8): severity, escalated by confirmed exploitation. This CVE's 7.8 is its impact severity (EG Severity), not escalated.
- EG Severity
- 7.8 HIGHCVSS-B, impact only: no KEV listing, EPSS or EG-KEV tier raises it.GitHub Security Advisory CVSS
- EG Likelihood
- 0.2% within 30 daysSource: FIRST EPSS. 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 every mission impact level.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, and whom BOD 26-04 binds: the SSVC and BOD 26-04 blocks below.
SSVC (CISA's decision table, applied by EchelonGraph)Track at every mission impact level.
A fix is available. Apply it within your standard update timelines.
Exploitation none (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.
The score's inputs: 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