GHSA-574f-3g2m-x479 Bouncy Castle for Java GOST 28147 CTR mode reuses keystream after 255 blocks

• Maven org.bouncycastle:bcprov-jdk14: >= 1.59, <= 1.80.1 (no fix yet) • Maven org.bouncycastle:bcprov-jdk15to18: >= 1.59, <= 1.80.1 (no fix yet) • Maven org.bouncycastle:bcprov-jdk18on: >= 1.59, < 1.80.2 → fixed in 1.80.2 • Maven org.bouncycastle:bcprov-debug-jdk14: >= 1.59, <= 1.80.1 (no fix yet) • Maven org.bouncycastle:bcprov-debug-jdk15to18: >= 1.59, <= 1.80.1 (no fix yet) • Maven org.bouncycastle:bcprov-debug-jdk18on: >= 1.59, <= 1.80.1 (no fix yet) • Maven org.bouncycastle:bcprov-ext-jdk14: >= 1.59, <= 1.78.1 (no fix yet) • Maven org.bouncycastle:bcprov-ext-jdk15to18: >= 1.59, <= 1.78.1 (no fix yet) • Maven org.bouncycastle:bcprov-ext-jdk18on: >= 1.59, <= 1.78.1 (no fix yet) • Maven org.bouncycastle:bcprov-ext-debug-jdk14: >= 1.59, <= 1.74 (no fix yet) • Maven org.bouncycastle:bcprov-ext-debug-jdk15to18: >= 1.59, <= 1.77 (no fix yet) • Maven org.bouncycastle:bcprov-ext-debug-jdk18on: >= 1.59, <= 1.77 (no fix yet) • Maven org.bouncycastle:bcprov-jdk14: 1.81.0 (no fix yet) • Maven org.bouncycastle:bcprov-jdk15to18: 1.81.0 (no fix yet) • Maven org.bouncycastle:bcprov-jdk18on: >= 1.81.0, < 1.81.1 → fixed in 1.81.1 • Maven org.bouncycastle:bcprov-debug-jdk14: 1.81.0 (no fix yet) • Maven org.bouncycastle:bcprov-debug-jdk15to18: 1.81.0 (no fix yet) • Maven org.bouncycastle:bcprov-debug-jdk18on: 1.81.0 (no fix yet) • Maven org.bouncycastle:bcprov-jdk14: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-jdk15to18: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-jdk18on: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-debug-jdk14: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-debug-jdk15to18: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-debug-jdk18on: >= 1.82, < 1.84 → fixed in 1.84 • Maven org.bouncycastle:bcprov-debug-jdk15on: <= 1.7.0 (no fix yet) • Maven org.bouncycastle:bcprov-jdk15on: <= 1.7.0 (no fix yet)

The GOST 28147-2015 CTR mode implementation (`G3413CTRBlockCipher`) in the Legion of the Bouncy Castle BC-JAVA `bcprov` core module only increments the final byte of the counter, so the counter wraps after 255 blocks and the keystream is reused. Reusing CTR keystream allows an attacker who can observe two ciphertexts produced with the same key/IV to recover the XOR of the plaintexts, breaking confidentiality. Affects BC-JAVA from 1.59 before 1.84 (with backported fixes in 1.80.2 and 1.81.1).