Malicious PDF — malware analysis report

Static analysis result for SHA-256 cf56b88143077029…

MALICIOUS

PDF

160.3 KB Created: 2021-07-12 23:37:11 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7dde4256edc25ddbac0e247a5fb24643 SHA-1: 52af346c91286279db589e30811a9a7a604147f8 SHA-256: cf56b881430770291be921376f0465dfcd1e6d3f4acb03bfc8e9f8aafd5a197c
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous links pointing 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 malware distribution. The document body is unreadable, but the heuristic firings and URL analysis are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9903

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://www.alongsideasia.com/wp-content/plugins/super-forms/uploads/php/files/cdab09fc0fe5d992fc9ea5b595b4805d/22468528059.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606eab9c70cb3---mexazudisirakotin.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/fefiksgrtt5nqbgjlvqatg38u6/3642629562.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607bfa18e06e6---25265829654.pdf
    • http://www.alwaysflorida.com/wp-content/plugins/formcraft/file-upload/server/content/files/160d21400d992a---63517534069.pdf
    • http://www.startservis.sk/novy/ckfinder/userfiles/files/zudagoxakejeletiramuketez.pdf
    • http://etasystem.net/userfiles/files/91158919776.pdf
    • http://freemansphotography.com/wp-content/plugins/formcraft/file-upload/server/content/files/160947b60c3ea2---25404762639.pdf
    • https://massagetheory.ca/wp-content/plugins/super-forms/uploads/php/files/5eede111d139f34ee0c480de45f92adb/10363969539.pdf
    • https://www.justgym.co.za/wp-content/plugins/super-forms/uploads/php/files/jdtmqe2plm46ss28585rsnble2/fewosiwurov.pdf
    • http://ziepniekkalns.lv/wp-content/plugins/formcraft/file-upload/server/content/files/16091e8a1c54f9---74921945449.pdf
    • https://aljazeerahpetroleum.ae/userfiles/files/wamepotawi.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16080873005410---wovorimixanefadapegi.pdf
    • http://hawks79.com/clients/85064/File/maboberisanedule.pdf
    • http://conservationenergy.com/wp-content/plugins/formcraft/file-upload/server/content/files/160aab5aa63244---sivegaz.pdf
    • http://alpha-cp.com/userfiles/file/55218365454.pdf
    • https://diedacorporation.net/freesiafiles/file/35017294280.pdf
    • https://hitourkorea.com/FileData/ckfinder/files/20210623_3D71B60497D4A9C8.pdf
    • http://leguido.net/files/52906640119.pdf
    • http://tksvolga.ru/userfiles/file/68252931726.pdf
    • https://alkalacarservice.com/public_html/userfiles/file/wexovururozekimu.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160bc7250d690a---77419933255.pdf
    • http://braintradingbcn.com/wp-content/plugins/super-forms/uploads/php/files/34a192a6c1252f368a969aaf8ed5c4e2/waminibanerolop.pdf
    • http://jfhconsultancy.nl/userfiles/files/79132962355.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=information+technology+for+management+turban+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_off00021022.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x21022 16792 bytes
font_01_sfnt_off00022834.bin
100f9b92b57bad68f422ab13d0112ab0819ba5717a1705a8b02c4f07338329d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x22834 18828 bytes
font_02_sfnt_off0002599c.bin
ccaa048c53506447c65fbdcdd12aa85f0b6da330c0b371ebfc7263db4c7074d1
pdf-font-stream PDF embedded font (sfnt) at offset 0x2599C 11204 bytes