Malicious PDF — malware analysis report

Static analysis result for SHA-256 bb4a5d77bfd1e3a2…

MALICIOUS

PDF

83.9 KB Created: 2021-10-04 14:18:59 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-21
MD5: be47ac18fb1bbe7406f535381aa16269 SHA-1: f0c13115a1f947be7c20787bef80631e9d495d88 SHA-256: bb4a5d77bfd1e3a28dca2e9f5b504ed4867b1004ee2f6b946cac6662d99fa678
156 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, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users to malicious content. The presence of external URIs and link farms indicates an attempt to lure users to external resources, likely for phishing or further malware delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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://laborke.ru/uplcv?utm_term=company+acquisitions+2020 PDF link annotation
    • https://hahapediatric.com/uploads/files/202109281156192415.pdfIn PDF document text
    • https://klingende-zeder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1614242da7fa32---virupitusukuxab.pdfIn PDF document text
    • http://bukharajohnscreek.com/sites/default/files/file/jemakaxiwopavukek.pdfIn PDF document text
    • http://aven.su/userfiles/file/sidakidotuzifotusadat.pdfIn PDF document text
    • http://stilistspb.online/public/files/uploads/files/75607524751.pdfIn PDF document text
    • http://imoroz.by/upload/file/5983681004.pdfIn PDF document text
    • https://campermagazine.tv/public/file/92280186433.pdfIn PDF document text
    • https://topclassgardening.nl/images/file/951126526.pdfIn PDF document text
    • http://fs-select.com/images/blog/file/84933496962.pdfIn PDF document text
    • https://ahirealty.in/admin/userfiles/files/voloteda.pdfIn PDF document text
    • https://eldorado777.ro/upload/editor/file/53057281603.pdfIn PDF document text
    • http://pmke.cz/pictures/files/rufobuwa.pdfIn PDF document text
    • https://bloc-immo.com/images/56646385717.pdfIn PDF document text
    • http://phunggia.biz/userfiles/file/12570408353.pdfIn PDF document text
    • https://mediaskills.rs/files/14156941813.pdfIn PDF document text
    • https://www.crossfitparamaribo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a07be8ea1f---2779607799.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/161321cbed5d59---98781851897.pdfIn PDF document text
    • https://literie-depot.fr/UserFiles/file/66036432061.pdfIn PDF document text
    • http://website-design-company.in/dev3/damodar/ckfinder/core/connector/php/userfiles/files/81884492387.pdfIn PDF document text
    • http://wedooverseas.com/userfiles/file/jaxitamadipo.pdfIn PDF document text
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/q9p9uleossvl0arbn5o4miiu01/vosazefizapezevibu.pdfIn PDF document text
    • http://oresteruggiero.com/userfiles/files/kelovome.pdfIn PDF document text
    • https://laughteronlineuniversity.com/images/upload/files/21905629880.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_off0000deaf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDEAF 10888 bytes
SHA-256: 329c3d6330dbf9691f26762c2fdce886111ad2f7f45a0c33e97cda6dd2fac295
font_01_sfnt_off0000f7f5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF7F5 19332 bytes
SHA-256: 9f915f40bf9373e0a7cf5af3771cb838bd72ac5d5ea95c68d30e531b390d44a3
font_02_sfnt_off000129d4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x129D4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1