Malicious PDF — malware analysis report

Static analysis result for SHA-256 04bc5b5441720974…

MALICIOUS

PDF

95.8 KB Created: 2021-07-05 01:14:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bd34090cd88692382ac3fab82f4c21ce SHA-1: 8fce9e4dc7d1a45f0f51e51c94569af299770fbe SHA-256: 04bc5b544172097406ac877a6a40be6a55d84ac47ca148d2a43852b235322516
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to potentially compromised websites or disposable hosting, suggesting it's used to distribute phishing content or further malware. The presence of multiple external URIs and link farm heuristics strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://chcial.ru/uplcv?utm_term=staar+test+2013+answers+key
    • http://sts-logistika.ru/wp-content/plugins/super-forms/uploads/php/files/c2d16bc3cf9efa9016ff97c86341a9c0/79120725574.pdf
    • https://www.schroedersales.com/wp-content/plugins/super-forms/uploads/php/files/875b824c118922de9f1bba667d907e6e/58973011452.pdf
    • https://autotronics.vn/userfiles/file/zazedutenadevodafidiz.pdf
    • http://tpdw.pl/userfiles/file/vurixo.pdf
    • https://travelselection.us/wp-content/plugins/formcraft/file-upload/server/content/files/160a05636d2ae2---25269390528.pdf
    • http://www.jcca.co.in/wp-content/plugins/formcraft/file-upload/server/content/files/160c8f1426a621---jidijogo.pdf
    • https://heykidsletscook.info/wp-content/plugins/super-forms/uploads/php/files/c007e5298522aab305108a53d9f4dfd1/vopusiwevelita.pdf
    • https://vinisfarm.com/wp-content/plugins/super-forms/uploads/php/files/3ecb1b22232dfb784657f4b49be619dd/kodexogawipiraju.pdf
    • https://edu-mate.kr/_UploadFile/Images/file/61586424204.pdf
    • https://szekszardportal.hu/userfiles/file/mopoxojenofelivinowuved.pdf
    • http://perfectthesale.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607db95968fff---xolararizeromexape.pdf
    • https://webgirls-studio.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a5ab6a8efa---218707866.pdf
    • http://www.sunarpazarlama.com/wp-content/plugins/super-forms/uploads/php/files/pm77s1dgs57tqd987r7egevgf2/24519309598.pdf
    • http://www.christinemartin.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160bac8d60b0e1---rezivobafifujenujujuruxa.pdf
    • https://sv-fin.ru/wp-content/plugins/super-forms/uploads/php/files/cd9b7c4c4919039acb6c63620b5e6595/63324441745.pdf
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c7ad1b01a0---27508837693.pdf
    • http://zulassungsservice4you.de/bilder/file/44179412406.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/e9eeaf41f1ed38449d4423d5faaf6c59/bafarunewunalaxijiluz.pdf
    • https://foodvellythailand.com/upload/files/kexusekug.pdf
    • https://vaytieudungtragop.com.vn/wp-content/plugins/super-forms/uploads/php/files/46v8mta523qidl3onn7mum11g4/68866513246.pdf
    • http://www.leesii.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9fe56abb01---bowadoretexizurajiwonaxi.pdf
    • https://bursaceviritercume.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abfff5dff86---bozedumot.pdf
    • https://pensiuneavalentina.ro/app/webroot/file/ruduxufidutejubavu.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_off000111ba.bin
9643a12324cf254090000817cba8a8ddc0c3754d7cc9dedc216b772a8c195496
pdf-font-stream PDF embedded font (sfnt) at offset 0x111BA 17452 bytes
font_01_sfnt_off00013fa8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x13FA8 16792 bytes
font_02_sfnt_off000157bf.bin
58c8d43726896c1eb5718cf9a2cf528b77138d5f96848b3cb858603686eab62f
pdf-font-stream PDF embedded font (sfnt) at offset 0x157BF 10676 bytes