Skip to content

PKCS7 Fixes #10128

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Open
kareem-wolfssl wants to merge 5 commits into
base: master
Choose a base branch
from
+35 −17
Open

PKCS7 Fixes #10128

Changes from all commits
Commits
Show all changes
5 commits
Select commit Hold shift + click to select a range
6693ea3
Ensure esd->signedAttribsCount contains the correct count in case som…
kareem-wolfssl Apr 3, 2026
c99bc5d
In wc_PKCS7_DecodeEnvelopedData, confirm encryptedContentTotalSz does…
kareem-wolfssl Apr 3, 2026
94955b1
Code review feedback
kareem-wolfssl Apr 3, 2026
ee8b654
Fix unused variable error
kareem-wolfssl Apr 6, 2026
6f6b6e7
Add additional checks for encryptedContentSz exceeding pkiMsgSz.
kareem-wolfssl Apr 6, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
52 changes: 35 additions & 17 deletions wolfcrypt/src/pkcs7.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -2196,7 +2196,6 @@ static int wc_PKCS7_BuildSignedAttributes(wc_PKCS7* pkcs7, ESD* esd,
#endif
word32 idx = 0;
word32 atrIdx = 0;
word32 cannedAttribsCount;

if (pkcs7 == NULL || esd == NULL || contentType == NULL ||
contentTypeOid == NULL || messageDigestOid == NULL ||
Expand All @@ -2219,8 +2218,6 @@ static int wc_PKCS7_BuildSignedAttributes(wc_PKCS7* pkcs7, ESD* esd,
return timeSz;
#endif

cannedAttribsCount = sizeof(cannedAttribs)/sizeof(PKCS7Attrib);

XMEMSET(&cannedAttribs[idx], 0, sizeof(cannedAttribs[idx]));

if ((pkcs7->defaultSignedAttribs & WOLFSSL_CONTENT_TYPE_ATTRIBUTE) ||
Expand Down Expand Up @@ -2252,10 +2249,10 @@ static int wc_PKCS7_BuildSignedAttributes(wc_PKCS7* pkcs7, ESD* esd,
idx++;
}

esd->signedAttribsCount += cannedAttribsCount;
esd->signedAttribsCount += idx;
esd->signedAttribsSz += (word32)EncodeAttributes(
&esd->signedAttribs[atrIdx], (int)idx, cannedAttribs,
(int)cannedAttribsCount);
(int)idx);
atrIdx += idx;
} else {
esd->signedAttribsCount = 0;
Expand Down Expand Up @@ -13223,6 +13220,13 @@ int wc_PKCS7_DecodeEnvelopedData(wc_PKCS7* pkcs7, byte* in,
}
wc_PKCS7_DecryptContentFree(pkcs7, encOID, pkcs7->heap);
} else {
word32 tmpSum;
if (!WC_SAFE_SUM_WORD32(idx, (word32)encryptedContentTotalSz, tmpSum) ||
tmpSum > pkiMsgSz) {
ret = BUFFER_E;
break;
}
Comment on lines +13223 to +13228
Copy link

Copilot AI Apr 6, 2026

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

The new bounds/overflow check for idx + encryptedContentTotalSz is a security-relevant behavior change, but there’s no regression test covering a malformed/truncated EnvelopedData where the encryptedContent length exceeds the remaining input. Add a decode-negative test vector (or construct one in the test) that previously would read past the input and now reliably returns BUFFER_E.

Copilot uses AI. Check for mistakes.

pkcs7->cachedEncryptedContentSz =
(word32)encryptedContentTotalSz;
pkcs7->totalEncryptedContentSz =
Expand Down Expand Up @@ -14352,9 +14356,17 @@ int wc_PKCS7_DecodeAuthEnvelopedData(wc_PKCS7* pkcs7, byte* in,
}

if (ret == 0) {
XMEMCPY(encryptedContent, &pkiMsg[idx],
word32 tmpSum;
if (!WC_SAFE_SUM_WORD32(idx, (word32)encryptedContentSz,
tmpSum) ||
tmpSum > pkiMsgSz) {
ret = BUFFER_E;
break;
} else {
XMEMCPY(encryptedContent, &pkiMsg[idx],
(word32)encryptedContentSz);
idx += (word32)encryptedContentSz;
idx += (word32)encryptedContentSz;
}
}
#ifndef NO_PKCS7_STREAM
pkcs7->stream->bufferPt = encryptedContent;
Expand Down Expand Up @@ -15270,16 +15282,22 @@ int wc_PKCS7_DecodeEncryptedData(wc_PKCS7* pkcs7, byte* in, word32 inSz,
}

if (ret == 0) {
XMEMCPY(encryptedContent, &pkiMsg[idx],
(unsigned int)encryptedContentSz);
idx += (word32)encryptedContentSz;

/* decrypt encryptedContent */
ret = wc_PKCS7_DecryptContent(pkcs7, encOID,
pkcs7->encryptionKey, pkcs7->encryptionKeySz,
tmpIv, expBlockSz, NULL, 0, NULL, 0,
encryptedContent, encryptedContentSz,
encryptedContent, pkcs7->devId, pkcs7->heap);
word32 tmpSum;
if (!WC_SAFE_SUM_WORD32(idx, (word32)encryptedContentSz, tmpSum) ||
tmpSum > pkiMsgSz) {
ret = BUFFER_E;
} else {
XMEMCPY(encryptedContent, &pkiMsg[idx],
(unsigned int)encryptedContentSz);
idx += (word32)encryptedContentSz;

/* decrypt encryptedContent */
ret = wc_PKCS7_DecryptContent(pkcs7, encOID,
pkcs7->encryptionKey, pkcs7->encryptionKeySz,
tmpIv, expBlockSz, NULL, 0, NULL, 0,
encryptedContent, encryptedContentSz,
encryptedContent, pkcs7->devId, pkcs7->heap);
}
if (ret != 0) {
XFREE(encryptedContent, pkcs7->heap, DYNAMIC_TYPE_PKCS7);
}
Expand Down
Loading