Malicious PDF — malware analysis report

Static analysis result for SHA-256 100a088655b9a198…

MALICIOUS

PDF

96.3 KB Created: 2021-06-25 22:14:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c18297db647877d83b71ea63c2eaa10c SHA-1: f6ebbdb376a2312acff5ba38a0246a452b9f0905 SHA-256: 100a088655b9a1980a63464251e6f3d23bba1d8ef8355055e8be78d6e130081a
156 Risk Score

Malware Insights

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

The PDF contains numerous links, many pointing to compromised WordPress upload directories, indicating a link farm designed to obscure the ultimate destination. The ML classifier and ClamAV detection strongly suggest malicious intent, likely for phishing or malware delivery. The presence of multiple external URIs and a link farm on disposable hosting further supports this assessment.

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 http://vasvaripalmuzeum.hu/upload/file/7062826212.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16076321d14353---tivevexipadosimus.pdf
    • https://www.lipfish.no/wp-content/plugins/formcraft/file-upload/server/content/files/160d045c49a95f---43725257675.pdf
    • https://itexpertdog.com/upload/files/labivakamozan.pdf
    • https://svetpoznaniyaonline.ru/wp-content/plugins/super-forms/uploads/php/files/f42bff3906198bcd705dab7d9977fa68/66059912567.pdf
    • http://www.gcsystem.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16079172dab752---satovumejubujuwa.pdf
    • https://makiriaszto.hu/ckfinder/userfiles/files/jodelawubepagudalux.pdf
    • https://dezsredstvompx.ru/wp-content/plugins/super-forms/uploads/php/files/839aa26cf7fc834d7c27fc2319d099af/korebagirase.pdf
    • http://kondicionery-ivanteevka.ru/upload_picture/file/47971018266.pdf
    • https://finestblogger.de/wp-content/plugins/super-forms/uploads/php/files/rkjcak3h97s0pqc4lj3v03baus/48971645428.pdf
    • http://xn--365-pn7mwb654m2qn.com/ckupload/files/69598506731.pdf
    • https://refundsrefunds.com/wp-content/plugins/formcraft/file-upload/server/content/files/160988cf0a0e15---taposuzitozupalegavibe.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/16096e640ae023---jawexipusujebebajoduke.pdf
    • https://amartzon.store/wp-content/plugins/super-forms/uploads/php/files/89454e3197ed5e906f886551acd0102e/rojiditezaluwi.pdf
    • https://leunamgroup.com/wp-content/plugins/super-forms/uploads/php/files/1b33b2bf208caaa54d0085027d407a4c/57176782251.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/ojfopob0o6at0nce7elqvgpsb0/81039666211.pdf
    • http://baodieptailor.com/uploads/2021-06-16/images/files/vunuse.pdf
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606c88e2b3a1a---5992746114.pdf
    • https://etonbio.com/newsLetters/images/file/guzarurofanawitive.pdf
    • https://nuregio.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606d327fb493f---91813750931.pdf
    • https://miamiuniquelimo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160709a3ba998d---73447418281.pdf
    • http://bogelaipigeon.com/upload/file/babiwew.pdf
    • http://garmagostaran.com/Upload/file/jafakapovemukoxemukuj.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/6naE_Nh8_CY/uplcv?utm_term=diazepam+and+naproxen
    • 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_off00011638.bin
17b43f5a3340585fa170018d6e54bd963edbedb5548a99f2b651f57272698b44
pdf-font-stream PDF embedded font (sfnt) at offset 0x11638 17608 bytes
font_01_sfnt_off000144a4.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x144A4 16792 bytes
font_02_sfnt_off00015cbb.bin
ab88b662e6904b679f4ace705776ada52140d77c9f6187917ae5cbeecbac75ea
pdf-font-stream PDF embedded font (sfnt) at offset 0x15CBB 10404 bytes