csirt@kutim:~/threat-intel/cve/CVE-2026-71884

Katalog CVE

CVSS 8.2 · High EPSS 0,41%

Kerentanan Reusing a Nonce, Key Pair in Encryption. Skor CVSS 4.0 8.2 (High) menurut CNA.

Deskripsi (NVD)

In Bouncy Castle for Java LTS before 2.73.13, the native one-shot CTR packet cipher did not check that the requested input length fitted the counter space the IV left. In CTR mode the IV and the block counter share one 16-byte block, so an IV of 13 to 15 bytes leaves a counter of only 1 to 3 bytes, addressing 256, 65536 or 16777216 blocks respectively. Given a longer input the counter wrapped and the keystream repeated from the start of the same packet, and the call then returned the full input length as though every byte had been correctly transformed. Two segments of the message were therefore encrypted under the same keystream, so their plaintexts can be recovered from the ciphertext alone, without the key, while the caller saw neither an exception nor a short length to indicate it. The streaming implementation validates at init and again while processing, and the portable AESCTRPacketCipher rejects such a request with "Counter in CTR/SIC mode out of range.", but the native one-shot path has a single entry point and performed no counter-range validation there. It now preflights the IV-derived counter range and rejects an over-long request before any output is written, so the operation is failure-atomic and never reports success for bytes it did not correctly transform. A counter of four bytes or more cannot be exhausted by a Java int length and is unaffected, as is a full 16-byte IV, where the counter range is the caller's responsibility. Bouncy Castle for Java (bcprov) is not affected, as it ships no native implementations.

Rincian

Terbit di NVD
9 Oktober 2026
Terakhir diubah
9 Oktober 2026
Status NVD
Awaiting Analysis
CVSS 4.0
8.2 (High), sumber CNA
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:X/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:Amber · uraikan di kalkulator
Jenis kelemahan (CWE)
CWE-323: Reusing a Nonce, Key Pair in Encryption
EPSS (30 hari)
0,41% peluang dieksploitasi; lebih tinggi dari 33,3% CVE lain

Produk dan versi terdampak

NVD belum mencantumkan data produk (CPE) untuk CVE ini. Produk yang terdampak biasanya disebut di deskripsi dan di advisory vendor pada daftar referensi.

Referensi dan perbaikan

Sumber: NVD · CVE.org · EPSS. Halaman ini disusun otomatis dari data tersebut; pembaruan terakhir 10 Okt 2026, 06:25 WITA. Kalau sistem di Perangkat Daerah memakai produk ini dan butuh bantuan, laporkan lewat kanal pelaporan.