Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4e50a5aa3648816…

MALICIOUS

PDF

85.1 KB Created: 2021-06-26 17:45:13 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 038138727a06288f4a40fec8e1ad5ce1 SHA-1: a2001ff1ea424a32e78163ebe8bbae1c88bb27e3 SHA-256: a4e50a5aa364881671bf74b4db3cfea3c318939a207683dde86652873a6291ea
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm on compromised WordPress sites, directing users to various external URLs. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the presence of numerous links to potentially malicious domains strongly suggests a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://catamma.ru/uplcv?utm_term=repudiation+definition+law
    • http://lichnyiybrand.ru/wp-content/plugins/formcraft/file-upload/server/content/files/16070371ccab64---88808968818.pdf
    • https://plswa.com/wp-content/plugins/super-forms/uploads/php/files/ec649c6aba29a778d3fb7b1b508592d4/gazegenixisojujudu.pdf
    • http://af.ssla.ru/images/fornews/files/88181426655.pdf
    • https://www.latentoac.com/portal/wp-content/plugins/super-forms/uploads/php/files/6ll9maeort9e1hu1plugli3jsa/pemumodabezimogaxatizo.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/kqpsf8tkl5utsn7ij14ev4mni4/74030604589.pdf
    • https://malimbe.africa/wp-content/plugins/super-forms/uploads/php/files/b0ebb4a6ce54e1a9fcfd660925fbb617/vitemepudederuzuxidogus.pdf
    • http://cdhsalumni.com/clients/28864/File/47168389544.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e52b8d2e7d---23597390879.pdf
    • https://www.myosiaffiliate.com/199trust/img/file/sewofavufiv.pdf
    • http://www.deco-interieure.com/userfiles/file/velezewolemuruvomukiba.pdf
    • https://baxsporthorses.com/userfiles/file/4135579458.pdf
    • http://mko-yug.ru/wp-content/plugins/super-forms/uploads/php/files/7839c3b9ec5a64be0b62fe71834615c5/wexexawukirasesumuk.pdf
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/160c413d531ead---govulosamoj.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c60b8b546c2---99025032810.pdf
    • http://bjoybrands.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082b81de77dd---57278381818.pdf
    • https://higher-reason.com/wp-content/plugins/super-forms/uploads/php/files/63uoqvflgod9257qt0v90vtnll/51543172402.pdf
    • http://kazenergy.kz/wp-content/plugins/formcraft/file-upload/server/content/files/16082bbbfeaf71---39949601962.pdf
    • https://humanistbeauty.com/wp-content/plugins/super-forms/uploads/php/files/jj1ubse2fd0fol37ltkocq3099/kipilikaduwejovami.pdf
    • http://syuncyoku.jp/upload/file/31792822518.pdf
    • https://sk-developers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f85154d57e---82745450534.pdf
    • http://gennarimaq.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1609ee0eb2f681---mibonexugafebitupu.pdf
    • http://15fratrowreunion.com/clients/2/2b/2b18ccadde375fd95e9ac2d5db5aaa67/File/tenoloburukegikolube.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000ea6b.bin
34941f6aeeca10a9f8c497b57f2ce42c20f02f305bd1b79d98232251a9951521
pdf-font-stream PDF embedded font (sfnt) at offset 0xEA6B 17132 bytes
font_01_sfnt_off0001171f.bin
604010d43061cfd4519e16f3b7da4e1e262251cad4591de27ba87b5fbe5fae6c
pdf-font-stream PDF embedded font (sfnt) at offset 0x1171F 10452 bytes
font_02_sfnt_off00012f03.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12F03 16792 bytes