{"id":90318,"date":"2026-05-06T19:01:44","date_gmt":"2026-05-06T19:01:44","guid":{"rendered":"https:\/\/dogewisperer.com\/?p=90318"},"modified":"2026-05-06T19:01:44","modified_gmt":"2026-05-06T19:01:44","slug":"litecoin-core-v0-21-5-5-release","status":"publish","type":"post","link":"https:\/\/dogewisperer.com\/?p=90318","title":{"rendered":"Litecoin Core v0.21.5.5 Release"},"content":{"rendered":"<div>\n<figure><img decoding=\"async\" alt=\"\" src=\"https:\/\/cdn-images-1.medium.com\/max\/1024\/1*gbnF8HSVCA6gdw73ZKhLQQ.png\"><figcaption>Inspired by artwork from: <a href=\"https:\/\/unsplash.com\/@guerrillabuzz\">https:\/\/unsplash.com\/@guerrillabuzz<\/a><\/figcaption><\/figure>\n<p>Litecoin Core version 0.21.5.5 is now available from:<\/p>\n<p><a href=\"https:\/\/download.litecoin.org\/litecoin-0.21.5.5\/\">https:\/\/download.litecoin.org\/litecoin-0.21.5.5\/<\/a>.<\/p>\n<p>This is a patch version release that includes important MWEB consensus hardening, node reliability improvements, wallet and mining fixes, and build\/test updates. This release includes important security updates. All node operators and wallet users are strongly encouraged to upgrade\u00a0ASAP.<\/p>\n<p>Please report bugs using the issue tracker at\u00a0GitHub:<\/p>\n<p><a href=\"https:\/\/github.com\/litecoin-project\/litecoin\/issues\">https:\/\/github.com\/litecoin-project\/litecoin\/issues<\/a><\/p>\n<h3><strong>Notable changes<\/strong><\/h3>\n<h3>Important MWEB\u00a0updates<\/h3>\n<p>This release contains important MWEB validation and state-handling fixes. Upgrading is recommended for all users, especially miners, pools, and nodeoperators using\u00a0MWEB.<\/p>\n<ul>\n<li>Added additional validation for MWEB inputs, pegins, HogEx data, kernel fees, and kernel lock heights (e7cbf1d, 42e7071, 8f8ad64, b9bd99a, 7564f05, a549004).<\/li>\n<li>Hardened MWEB amount and fee calculations against overflow and invalid edge cases (42e7071, 1cd94bb).<\/li>\n<li>Added fallback handling for rare hash-to-secret-key cases so derived MWEB keys are valid scalars (773c138).<\/li>\n<li>Added consensus parameters for known frozen or approved MWEB transactions and outputs needed to keep MWEB state balanced (1dcbf3f, 17f16ce, 66f6856).<\/li>\n<li>Improved handling of mutated or invalid MWEB block data so invalid data does not leave stale block data or mutate cached chainstate (742ee94, ff309cd, 17f16ce).<\/li>\n<li>Updated MWEB chainstate during block replay and crash recovery (bbd3b78).<\/li>\n<\/ul>\n<h3>Network and policy\u00a0changes<\/h3>\n<ul>\n<li>Increased the maximum P2P protocol message length to 32 MB so valid MWEB blocks and messages fit under the message-size limit (457bcd7).<\/li>\n<li>Enforced standard script policy checks for pegout scripts (c25bf89).<\/li>\n<\/ul>\n<h3>Mining changes<\/h3>\n<ul>\n<li>Avoid reading the previous block from disk when constructing HogEx transactions; use MWEB data already stored in the block index (873d9d2).<\/li>\n<li>Improved getblocktemplate fee and sigop accounting for transactions carrying MWEB data (873d9d2).<\/li>\n<li>Avoid including MWEB transactions in candidate blocks when their input and output commitments would sum to zero (f423a84).<\/li>\n<\/ul>\n<h3>Wallet and RPC\u00a0changes<\/h3>\n<ul>\n<li>Fixed MWEB balance and pegout accounting (1dcbf3f, 1cc1cee).<\/li>\n<li>Added MWEB view keys to dumpwallet (eae9e47).<\/li>\n<li>Supported maxfeerate=0 for MWEB transactions in sendrawtransaction and testmempoolaccept (8782ab9).<\/li>\n<li>Allowed getblocktemplate on test chains when the node is unconnected or in initial block download (455aff8).<\/li>\n<\/ul>\n<h3>Bug fixes<\/h3>\n<ul>\n<li>Fixed MWEB PMMR rewind corruption and improved MMR file write durability (23e5eac, bf25a7c, 3110a7e).<\/li>\n<li>Fixed a cache leaf bounds check (6dd2952).<\/li>\n<li>Fixed a transaction index consistency issue that could occur if writing block data failed after the index commit (eb7f68a).<\/li>\n<li>Fixed wallet loading with Boost 1.78 and newer (3c3aedb, c882663).<\/li>\n<li>Fixed a debug build logger symbol conflict and made MWEB logger initialization safer (6fc0530, b4c0037).<\/li>\n<\/ul>\n<h3>Build and test\u00a0changes<\/h3>\n<ul>\n<li>Added missing &lt;cstdint&gt; includes needed by some compilers (58f89ba).<\/li>\n<li>Replaced the functional test dependency on the external litecoin_scrypt Python package (d139222).<\/li>\n<li>Added and expanded tests for MWEB P2P messages, duplicate pegins, crash recovery, mutated blocks, mining, and wallet\/RPC behavior.<\/li>\n<li>Normalized line endings in selected documentation, Qt resources, and fuzz test files (dcc7bc5).<\/li>\n<li>Fixed the broken Transifex link in the README (0f5f7d5).<\/li>\n<\/ul>\n<h3>Hashes for verification<\/h3>\n<p>These are the SHA-256 hashes of the released\u00a0files:<\/p>\n<pre>3561a1f0ff8db311e4f18553020f625d5547f5bfe9eade8671b9c63aa5f7462a  litecoin-0.21.5.5-aarch64-linux-gnu.tar.gz<br>a117a3f8f699b85cb551f318d37cd06d43839b81a658e39287c2c511e6d51bd9  litecoin-0.21.5.5-arm-linux-gnueabihf.tar.gz<br>0f4c9bd28bb17680c9a68f8244da03d899634cb9470c2fa18ab16ce53d44993a  litecoin-0.21.5.5-riscv64-linux-gnu.tar.gz<br>623410d4f2695a68aa71332ae0672fee19276f41c1c63a531f97e24a50edde14  litecoin-0.21.5.5-x86_64-linux-gnu.tar.gz<br>f522e6f93a48a884a0a536e1f1785b5daaed21abcd5b8c46cd9c9046d7e727d9  litecoin-osx-signed.dmg#<br>9d222bf96eed1c209e4f57b278f11d9a5266fb2c6caedc23c4a8f4b421288c70  litecoin-0.21.5.5-win64-setup.exe<\/pre>\n<h3>Credits<\/h3>\n<p>Thanks to everyone who directly contributed to this\u00a0release:<\/p>\n<ul>\n<li><a href=\"https:\/\/github.com\/DavidBurkett\/\">David Burkett<\/a><\/li>\n<li><a href=\"https:\/\/github.com\/losh11\">Loshan<\/a><\/li>\n<\/ul>\n<p><img loading=\"lazy\" decoding=\"async\" src=\"https:\/\/medium.com\/_\/stat?event=post.clientViewed&amp;referrerSource=full_rss&amp;postId=eb81cbee0fa5\" width=\"1\" height=\"1\" alt=\"\"><\/p>\n<hr>\n<p><a href=\"https:\/\/blog.litecoin.org\/litecoin-core-v0-21-5-5-release-eb81cbee0fa5\">Litecoin Core v0.21.5.5 Release<\/a> was originally published in <a href=\"https:\/\/blog.litecoin.org\/\">Litecoin Project<\/a> on Medium, where people are continuing the conversation by highlighting and responding to this story.<\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"<p>Inspired by artwork from: https:\/\/unsplash.com\/@guerrillabuzz Litecoin Core version 0.21.5.5 is now available from: https:\/\/download.litecoin.org\/litecoin-0.21.5.5\/. This is a patch version release that includes important MWEB consensus hardening, node reliability improvements, wallet and mining fixes, and build\/test updates. This release includes important security updates. All node operators and wallet users are strongly encouraged to upgrade\u00a0ASAP. Please report [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"iawp_total_views":0,"footnotes":""},"categories":[2],"tags":[3,4,5],"class_list":["post-90318","post","type-post","status-publish","format-standard","hentry","category-news","tag-crypto","tag-doge","tag-news"],"_links":{"self":[{"href":"https:\/\/dogewisperer.com\/index.php?rest_route=\/wp\/v2\/posts\/90318","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/dogewisperer.com\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/dogewisperer.com\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/dogewisperer.com\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/dogewisperer.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=90318"}],"version-history":[{"count":0,"href":"https:\/\/dogewisperer.com\/index.php?rest_route=\/wp\/v2\/posts\/90318\/revisions"}],"wp:attachment":[{"href":"https:\/\/dogewisperer.com\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=90318"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/dogewisperer.com\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=90318"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/dogewisperer.com\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=90318"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}