cbcvebase.
CVE-2026-0819
published 2026-03-19

CVE-2026-0819: A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom…

PriorityP433high7.1CVSS 3.1
AVLACLPRLUINSUCNIHAH
EPSS
0.10%
1.1th percentile
A stack buffer overflow vulnerability exists in wolfSSL's PKCS7 SignedData encoding functionality. In wc_PKCS7_BuildSignedAttributes(), when adding custom signed attributes, the code passes an incorrect capacity value (esd->signedAttribsCount) to EncodeAttributes() instead of the remaining available space in the fixed-size signedAttribs[7] array. When an application sets pkcs7->signedAttribsSz to a value greater than MAX_SIGNED_ATTRIBS_SZ (default 7) minus the number of default attributes already added, EncodeAttributes() writes beyond the array bounds, causing stack memory corruption. In WOLFSSL_SMALL_STACK builds, this becomes heap corruption. Exploitation requires an application that allows untrusted input to control the signedAttribs array size when calling wc_PKCS7_EncodeSignedData() or related signing functions.

Affected

5 ranges
VendorProductVersion rangeFixed in
debianwolfssl< wolfssl 5.9.0-0.1 (forky)wolfssl 5.9.0-0.1 (forky)
msrcazl3_mariadb_10.11.16-1_on_azure_linux_3.0
msrccbl2_mariadb_10.6.24-1_on_cbl_mariner_2.0
wolfsslwolfssl>= 0 < 5.9.0-0.15.9.0-0.1
wolfsslwolfssl>= 5.5.0 < 5.9.05.9.0

CVSS provenance

nvdv3.17.1HIGHCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:H
nvdv4.02.2LOWCVSS:4.0/AV:L/AC:L/AT:P/PR:N/UI:N/VC:N/VI:H/VA:H/SC:N/SI:N/SA:N/E:U/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
osv2.2LOW
vendor_debian2.2LOW
vendor_msrc2.2LOW
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