Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b07d6e6a827a6fc…

MALICIOUS

PDF

81.3 KB Created: 2021-07-26 14:58:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1d8813117171766b02a104023f036f7a SHA-1: 68793886b745cca8393a204fc2904cb84566901c SHA-256: 4b07d6e6a827a6fc20836b9f6733a88e3f8aa3b380fa206e9ad1e3b191d08b92
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites. Heuristics indicate this is a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9987

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 http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c892e7b7b0---37335553321.pdf
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160beedb568761---23130611332.pdf
    • https://engravestone.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607c795805905---tokususerorujerizazowi.pdf
    • https://free-spirit-city.eu/uploads/wysiwyg/files/sijisirafiwugapituno.pdf
    • http://conwaychristian.org/wp-content/plugins/formcraft/file-upload/server/content/files/160ca3c9f18bcc---94531199393.pdf
    • https://vuaship.com/wp-content/plugins/super-forms/uploads/php/files/acji99utibrks4hn8cehhnisbv/16508712270.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16082a229925a5---71905648586.pdf
    • http://jar-ted.pl/file/porebasaxamuzokaponepawa.pdf
    • http://droneducational.com/admin/userfiles/file/90560299306.pdf
    • http://wenxuezj.com/images/File/36746530748.pdf
    • http://hzdshg.com/images/upload/File/gemisewipubulot.pdf
    • https://apoc.com.au/wp-content/plugins/super-forms/uploads/php/files/16c51b28e16bb1b23903ddd3f2a0d47a/xusavilajixaz.pdf
    • http://primaria-ciocirlia.ro/media/file/jenelufuxuzagamuxufi.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c2aef84354---lirenofiletafupumanuxitos.pdf
    • http://seanmore.com/userData/board/file/17038103241.pdf
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160abc0f438ecd---xosapaxudegubenima.pdf
    • http://lifestyleufa.ru/wp-content/plugins/super-forms/uploads/php/files/1a6c63323b40b636b5d2cc037ff75be1/94407349607.pdf
    • https://htddienstverlening.nl/userfiles/file/pewibo.pdf
    • http://tramtronbetong.com/uploads/userfiles/file/23080811975.pdf
    • http://ciccioinpentola.com/userfiles/files/19689142614.pdf
    • http://skolicka.eu/foto/images/file/kuxojaxobagaj.pdf
    • https://acavacecio.it/userfiles/files/23303246767.pdf
    • https://stewsites.com/wp-content/plugins/super-forms/uploads/php/files/ce9505f9d55a68d386d1b3c76435b3c7/kizesoruzu.pdf
    • https://www.a2zmedical.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/16097e4af2164c---bitibalu.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=cuadernillo+de+repaso+escolar+cuarto+grado+contestado+2020
    • 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_off0000d348.bin
3a2185007aab2771f65751ded6dee219f73c985744682f204e70cf124901fb70
pdf-font-stream PDF embedded font (sfnt) at offset 0xD348 11060 bytes
font_01_sfnt_off0000ecf7.bin
0cb6589d1199fe68601c05078cd0de37e06466adbeda27f94331b0ddf45596ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xECF7 18844 bytes
font_02_sfnt_off00011c5c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C5C 16792 bytes