Malicious PDF — malware analysis report

Static analysis result for SHA-256 f5a8385f0d2f30ae…

MALICIOUS

PDF

88.9 KB Created: 2021-07-14 04:15:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: 4b882cd8f4d3a61b97c3279ff362b394 SHA-1: b1310acc5f4edc1fc7c80f96005c9863b5e17a94 SHA-256: f5a8385f0d2f30ae405b4e78b4998995aa99f2055ad73acf15569ac6204ad182
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or distributing further malware. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9822

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://vakukh.ru/wp-content/plugins/super-forms/uploads/php/files/a5f529bb2f91265498485a3ac316a19d/40554419412.pdf In PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/160b9ce5e0ba0f---79143776862.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a4c22fd2b6b---32860487232.pdfIn PDF document text
    • https://solarconsulting.org/wp-content/plugins/super-forms/uploads/php/files/1723defaa5b244eb45149bc6aef545d8/4685873092.pdfIn PDF document text
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1608c1bca7a5ea---bofevajanosexi.pdfIn PDF document text
    • https://aadhaarretail.com/administrator/imagetemp/file/bilekazefizepupe.pdfIn PDF document text
    • https://khotelmarket.com/FileData/ckfinder/files/20210608_FCA7A1A5235CF484.pdfIn PDF document text
    • https://pasarantogeldua.com/contents//files/jelezuzikusizezaxog.pdfIn PDF document text
    • http://www.linkkorea.co.kr/wp-content/plugins/formcraft/file-upload/server/content/files/1607408f6a5d0c---zafokufuzabubudizelolixeb.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16071a039cad8e---43924401438.pdfIn PDF document text
    • https://www.psalighting.com/wp-content/plugins/super-forms/uploads/php/files/40d316eede689e207921b1b9f7fa3e45/86031987461.pdfIn PDF document text
    • https://www.saenger-ohg.de/wp-content/plugins/formcraft/file-upload/server/content/files/1607aaeed09718---nazomuf.pdfIn PDF document text
    • https://www.costaverde.it/wp-content/plugins/formcraft/file-upload/server/content/files/16092e9468a790---1149623592.pdfIn PDF document text
    • http://seoulsquare.com/userfiles/file/43522402604.pdfIn PDF document text
    • https://www.frankcapassoandsons.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c29a5372554---rimisiwupujojekekodirij.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/234c0bed91a209409cb454df6332b3a9/vimekagenapibosoxirowavug.pdfIn PDF document text
    • http://www.cascinasorigherio.it/wp-content/plugins/formcraft/file-upload/server/content/files/160984249cc29e---luduziritemuj.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/aipv8spq0m6bd5t29tk4lrto75/97295171304.pdfIn PDF document text
    • http://vector-luczak.pl/new/fck_user_files/file/wovijusafixajo.pdfIn PDF document text
    • http://capri.lt/userfiles/files/pufowufesepob.pdfIn PDF document text
    • http://amon-syotengai.com/userfiles/file/385293564.pdfIn PDF document text
    • https://rffsev.ru/wp-content/plugins/super-forms/uploads/php/files/6764a6791cb43abd737e1a096c62521c/59302939746.pdfIn PDF document text
    • http://hkt-optics.com/hkt/images/userfiles/file/rirupupokolaxoxowagigar.pdfIn PDF document text
    • https://vildmarksjagt.dk/userfiles/file/91779385140.pdfIn PDF document text
    • http://test.uebersetzungen-nesselberger.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d7c3c6f152---zovawupakimiworatenalagot.pdfIn PDF document text
    • https://www.kadeavenue.com/wp-content/plugins/super-forms/uploads/php/files/cce2d5563c41d6f4783ab5a54d145820/fakodaxarexubavened.pdfIn PDF document text
    • https://erdemlerkoleji.com/resimler/files/xemizi.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BkSY9tpko7c/uplcv?utm_term=highway+maintenance+notesPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000f8a5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF8A5 10724 bytes
SHA-256: dfbfaabbd333028e1d31d24000f2196d9d52a6a7c5f9199572e4f2ee5d2fafc9
font_01_sfnt_off00011122.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11122 17276 bytes
SHA-256: 8112a3db4b20a318a7ef08e672e9f661ed27a6b4f82ce9c6cd53c89631be18ef
font_02_sfnt_off00013e31.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E31 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1