Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8b2fb27bd1cedca…

MALICIOUS

PDF

81.6 KB Created: 2021-09-20 22:10:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: 461d0d521d6911e6b33ca04ea942e816 SHA-1: 41793d5b19c576f1350525115db224dd717c2f38 SHA-256: a8b2fb27bd1cedcadc04c3b09f78406bf9880282893888be4ca46ad4b689e7f9
126 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to a link farm hosted on disposable domains, suggesting a phishing or malware distribution campaign. The PDF_SEO_DISPOSABLE_LINK_FARM heuristic indicates a deliberate attempt to create a large number of links on low-reputation hosting.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 5

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://allytemp.ru/uplcv?utm_term=excel+hex+to+binary PDF link annotation
    • http://santeh.md/img/files/22253018560.pdfIn PDF document text
    • http://www.armstrongre.com/files/files/28192510153.pdfIn PDF document text
    • https://hotelcorona.ro/files/vewuko.pdfIn PDF document text
    • https://www.cascatai.com.br/ckfinder/userfiles/files/lumakadatatuworebu.pdfIn PDF document text
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/161362d5a2df96---98363233302.pdfIn PDF document text
    • https://tecnibat.net/uploads/archivos/lenutaxitenamesekarumami.pdfIn PDF document text
    • http://lighthouse-connection.at/myPix/file/nelolume.pdfIn PDF document text
    • http://machulski.com/public/file/laxovuvasif.pdfIn PDF document text
    • https://dol-rtknetwork.com/uploads/files/xaroviban.pdfIn PDF document text
    • http://galettedesrois.hu/userfiles/file/77593069506.pdfIn PDF document text
    • http://ysmenmidwestindia.org/uploads/userfiles/file/file/8005067555.pdfIn PDF document text
    • https://promenade-perpignan.com/userfiles/file/pizijixex.pdfIn PDF document text
    • http://suchanekstomatolog.pl/files/file/2304795345.pdfIn PDF document text
    • https://fullgame.hu/uploads/files/rokizu.pdfIn PDF document text
    • https://andrejc.si/files/file/4768719730.pdfIn PDF document text
    • https://bauarch.bg/files/37267569858.pdfIn PDF document text
    • http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613e7f99ac044---26249588857.pdfIn PDF document text
    • http://de.ruben.pl/ckfinder/userfiles/files/88516262377.pdfIn PDF document text
    • http://ecohort.com/userfiles/files/valemurolideruworaf.pdfIn PDF document text
    • http://goodwill.pl/userfiles/file/99997081255.pdfIn PDF document text
    • http://ihanzao.com/userfiles/file/20210904144539_219515617.pdfIn PDF document text
    • https://pepsima.biz/files/file/xikumefobojugino.pdfIn PDF document text
    • https://etravelbox.com/scgtest/team-explore/uploads/files/15167631799.pdfIn PDF document text
    • https://mallarpurnaisuva.org/go/file/46634109707.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_off0000d891.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD891 18400 bytes
SHA-256: c9ba4819fb2f32b29d4b0b89aa117de3c7bb6d07c59352d6b8198a3d4d9bbe29
font_01_sfnt_off000108fc.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x108FC 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00012113.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12113 10500 bytes
SHA-256: 4ee48aa408f4bea551ea06e28417a63e88f68a86e99e4c03e046ec073b2588d2