Malicious PDF — malware analysis report

Static analysis result for SHA-256 f8071da32289f5e4…

MALICIOUS

PDF

80.1 KB Created: 2021-09-21 03:25:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 996306780043daae21bc006c03c1c4ed SHA-1: 70c5146d3cd85a2c9d39fc015e4d1585133e251d SHA-256: f8071da32289f5e4ea852ce5489c5281ea71a99a7890d5030657bb972f4f0453
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to a variety of domains, many of which appear to be part of link farms or hosted on compromised infrastructure. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or directing users to malicious content. The presence of external URI links and link farm heuristics suggests an attempt to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://philabc.ru/uplcv?utm_term=how+to+save+pdf+without+comments PDF link annotation
    • http://gyarmatilovastorna.hu/userfiles/file/93829263531.pdfIn PDF document text
    • http://888chji.com/userfiles/files/wipifekumusute.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/wugojuxetesonafigitarosiz.pdfIn PDF document text
    • http://sbs-group.co/userfiles/files/42170824625.pdfIn PDF document text
    • http://carbonelite.ru/file/62805388013.pdfIn PDF document text
    • http://schouteninterieurwerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16140bf5a62119---ratawebonunixori.pdfIn PDF document text
    • https://www.traveltimevipp.com/wp-content/plugins/super-forms/uploads/php/files/04d569ae5beb54f788cddfb4b12f0eec/fokugemigalegojuvewikag.pdfIn PDF document text
    • http://darec.sk/files/files/76282596551.pdfIn PDF document text
    • http://scpt.it/userfiles/files/wigutudaw.pdfIn PDF document text
    • https://k-barrierfree.com/FileData/ckfinder/files/20210904_F48FD5BAD19697EF.pdfIn PDF document text
    • https://rmp-traueranzeigen.de/cms/files/nagekizikezasezufuwa.pdfIn PDF document text
    • https://amesmedicalservices.com/wp-content/plugins/formcraft/file-upload/server/content/files/161425379a3733---49254740239.pdfIn PDF document text
    • http://efckrakow.pl/userfiles/file/zadobetepopufu.pdfIn PDF document text
    • http://thuaphatlailongthanh.vn/upload/contentFile/minhchau/file/64118435523.pdfIn PDF document text
    • http://www.thunderesp.com/ckfinder/ckfinder.htmlfiles/dovibipomiwej.pdfIn PDF document text
    • https://www.potravinyav21.cz/ckfinder/userfiles/files/befibimi.pdfIn PDF document text
    • https://philly.drinkpoint.com/uploads/files/51705604268.pdfIn PDF document text
    • http://cdkuys.handysociality.com/upload/files/lomimegalutogaxamak.pdfIn PDF document text
    • https://plewmal-d.com/Uploads/files/83414289553.pdfIn PDF document text
    • https://hongdung.vn/ckeditor/images/files/51613535283.pdfIn PDF document text
    • http://romengo.com/ckfinder/userfiles/files/26760299203.pdfIn PDF document text
    • http://vodnik48.ru/content/file/9552729077.pdfIn PDF document text
    • https://www.xyoaa.org/sites/default/files/files/88563580973.pdfIn PDF document text
    • http://haitrungkim.vn/uploads/userfiles/file/ruvet.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000d393.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD393 10980 bytes
SHA-256: 97d7bcaf175c736b506ea460e85ac6f074602b7f0d79135f4db371573194382c
font_01_sfnt_off0000ecea.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xECEA 17708 bytes
SHA-256: e6767185c88e0a8ee3ce89a387b7993efdfc09236fed9d7f01bcaf77b6c0b13c
font_02_sfnt_off00011a6d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A6D 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1