Malicious PDF — malware analysis report

Static analysis result for SHA-256 c57b555d3efbe6ac…

MALICIOUS

PDF

85.3 KB Created: 2021-06-26 13:42:48 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 73f8642c1c300c3bd80e29d3b6eaac17 SHA-1: 0d8c5ce13965202a0f58608810e62149e182eb42 SHA-256: c57b555d3efbe6acb668705e143985580a8f5d0c9a87af4251b1b2b3f1be17fe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, specifically identified as a phishing trojan. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with phishing lures and potential malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://drafthe.ru/uplcv?utm_term=sample+paper+class+12+with+solution
    • http://statewideroadservices.com/clients/879378/File/tuxalupevefavade.pdf
    • http://haus-st-otmar.ch/userfiles/files/56798430130.pdf
    • https://appfacile.it/file/tojosevonaf.pdf
    • https://www.dynasil.com/wp-content/plugins/super-forms/uploads/php/files/6f9081469dec73acdce2f10b565db2a4/69439953261.pdf
    • https://expresstestingatl.com/wp-content/plugins/super-forms/uploads/php/files/51eba92d05d20f42cb60f87f4736f403/vunageposiditoliw.pdf
    • https://prestinireedcorp.com/userfiles/files/67647771682.pdf
    • https://kalatranslation.co.uk/wp-content/plugins/super-forms/uploads/php/files/8qvu6lsp3koela7etgoej99p4q/31621576579.pdf
    • http://amdind.com/userfiles/file/89314887658.pdf
    • http://www.veronicaneal.com/wp-content/plugins/formcraft/file-upload/server/content/files/1/16075ae507a3cb---bimokodiguvogasoxo.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/mtpiklrgp003qr2psneumq4hgb/wejofifozexeveb.pdf
    • https://saraelv.no/wp-content/plugins/formcraft/file-upload/server/content/files/160747dcd54667---34024495029.pdf
    • https://k-kompany.ru/wp-content/plugins/super-forms/uploads/php/files/7b66188744d2a80fed7c46516a82e50b/dasasolotisavaf.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/453bcbac69f7f38199e3fbfeffe76202/85865582127.pdf
    • http://zekidilektekstil.com/images_upload/files/zavege.pdf
    • https://sunrise-photon.com/upfiles/editor/files/sadigurafasabinove.pdf
    • https://nationalcardsolutions.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f43b9306fa---35188131089.pdf
    • http://rajakedua.com/contents//files/45377933160.pdf
    • https://ailani.org/wp-content/plugins/super-forms/uploads/php/files/fc11a862e76327f818851762658a175b/nuwepodubuxaxuwam.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/2115aacdbf2e51fab4522fe2e0b56ee2/81937002822.pdf
    • http://autohondl.cz/userfiles/file/92567780082.pdf
    • https://cananalimdar.com/wp-content/plugins/super-forms/uploads/php/files/ij1pdsiohoh2h8m7pglkq14vge/wikebokudibuwuxatenajel.pdf
    • https://ontime-taxi.kg/wp-content/plugins/super-forms/uploads/php/files/46a7440091964379958cb83bf6385365/81786163241.pdf
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/s58q1fdov5amns1b0djunvjam9/norarobuxotafugowil.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16b1679998---68979994907.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_off0000e9b0.bin
5facab34fe75e6b993130630eb7c05238b9f2de03bf0648ebb435c8ac261e5e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9B0 11072 bytes
font_01_sfnt_off00010368.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10368 16792 bytes
font_02_sfnt_off00011b7a.bin
4e02113f883f9531d1b973d4f7aeaa96ea075daeefbb20cb13f3af31a3f1ca47
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B7A 16972 bytes