Malicious PDF — malware analysis report

Static analysis result for SHA-256 3c857dcd1add56b4…

MALICIOUS

PDF

87.7 KB Created: 2021-07-01 21:15:20 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67131d19bd2e1b0597963f67b5fd4944 SHA-1: 5e7aacb5f5126091a818d6fa773789ddd9d27443 SHA-256: 3c857dcd1add56b4b0d8735b153888872c51875f517f0056ac3b15cb3f63911c
156 Risk Score

Malware Insights

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

The file was identified as malicious by ML classifiers and ClamAV, detecting it as a phishing trojan. Static analysis revealed it functions as a link farm, with numerous URLs pointing to compromised WordPress sites and disposable hosting. These links are likely intended to redirect users to malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9966

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://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/160973e5dc1ed8---zesipozomibazodomanap.pdf
    • https://masterok-kovka.ru/wp-content/plugins/super-forms/uploads/php/files/845c1ee60003711cadcf29a21f6136c6/42892154994.pdf
    • http://andlupa.com/userfiles/file/59295969289.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/bb426d14a8df34b9769d405166f88efc/27384034737.pdf
    • https://www.clubmanizales.com.co/wp-content/plugins/formcraft/file-upload/server/content/files/1609f8edab3982---31372516161.pdf
    • http://sparan-art.ru/ckfinder/userfiles/files/bizupuga.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abf9999cb71---napoxisenafikudemilevi.pdf
    • http://zap-interactive.com/uploads/files/jizududigowonidod.pdf
    • http://ronaldtan.nl/images/photo/baxobuzototota.pdf
    • https://www.rekalibracija.com/wp-content/plugins/super-forms/uploads/php/files/3dd9a2bb0ee75e34776e14e99a353677/75504807333.pdf
    • https://samsungvrvklima.com/upload/ckfinder/files/gorunusexowavitugopugi.pdf
    • https://lerong.vn/wp-content/plugins/super-forms/uploads/php/files/f640171daa64c4682bfd0abfd0dc1b62/dedipiwakalagad.pdf
    • https://sieompaysdebray.fr/lesiom/txt/imgadmin/file/24236062331.pdf
    • https://kvgrup.com.ua/wp-content/plugins/formcraft/file-upload/server/content/files/160c6bde680339---44292532870.pdf
    • http://stroynerud-sm.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1607264092e82e---fuvobukunaxexesavi.pdf
    • http://md-servicios.com/userfiles/file/82807765898.pdf
    • https://mollis.rs//files/lelugedufijafowud.pdf
    • http://douzonebnf.com/upload/file///15720071034.pdf
    • http://thedewakohchang.com/image/upload/File/oxujumajapitinokanusu.pdf
    • http://johnsonsdynastyincfamilyassociation.com/clients/10108/File/8244756592.pdf
    • https://transcendenceit.com/wp-content/plugins/super-forms/uploads/php/files/ca374ad70793d39908a505f2262eb06c/xiligoguka.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/6naE_Nh8_CY/uplcv?utm_term=condolence+bible+verses+for+loss+of+father
    • 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_off0000f4aa.bin
99c3b64413e8c0c1816b2ef5a226dd2da77991634efd85d407f49b7d2b1badea
pdf-font-stream PDF embedded font (sfnt) at offset 0xF4AA 17088 bytes
font_01_sfnt_off000120cf.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x120CF 16792 bytes
font_02_sfnt_off000138e6.bin
2dd15b323c8cc3c49036dc0ffe871fd81006dccd2d0f0b7baf50040f2866a494
pdf-font-stream PDF embedded font (sfnt) at offset 0x138E6 10812 bytes