From: Miod Vallat <miod.vallat@powerdns.com>
Date: Wed, 4 Feb 2026 06:00:16 +0000 (+0100)
Subject: Correctly compute public key exponent length when larger than 255.
X-Git-Tag: rec-5.5.0-alpha0~38^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F16810%2Fhead;p=thirdparty%2Fpdns.git

Correctly compute public key exponent length when larger than 255.

Signed-off-by: Miod Vallat <miod.vallat@powerdns.com>
---

diff --git a/pdns/opensslsigners.cc b/pdns/opensslsigners.cc
index 3a8df543b1..fb4daf6aec 100644
--- a/pdns/opensslsigners.cc
+++ b/pdns/opensslsigners.cc
@@ -941,7 +941,7 @@ void OpenSSLRSADNSCryptoKeyEngine::fromPublicKeyString(const std::string& conten
     if (contentLen < 3) {
       throw runtime_error(getName() + " invalid input size for the public key");
     }
-    const size_t exponentSize = raw[1] * 0xff + raw[2];
+    const size_t exponentSize = (static_cast<size_t>(raw[1])) * 0x100 + raw[2];
     if (contentLen < (exponentSize + 4)) {
       throw runtime_error(getName() + " invalid input size for the public key");
     }