Malicious PDF — malware analysis report

Static analysis result for SHA-256 20556a595ac06049…

MALICIOUS

PDF

69.3 KB Created: 2021-09-25 07:26:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 0b28e93e44791121f7a81045711397c1 SHA-1: 8ca029bfb846ac110270de6e48a7f5d55b9ee86e SHA-256: 20556a595ac0604905c5735a431849b11bd90056d43d533143732c924e4bd588
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with several heuristics indicating it functions as a link farm. Notably, some links point to compromised WordPress upload storage, suggesting a potential distribution mechanism for further malicious content. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9771

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://beaszemin.com/files/2397755175.pdf
    • http://lammermoor.net/imagenes/file/1685126883.pdf
    • https://accidentmatters.com/ckfinder/userfiles/files/88775292245.pdf
    • http://pocatellocampfire.com/wp-content/plugins/super-forms/uploads/php/files/4qftpft53v8qss8eg0rldcq5c7/wevijenudogexitiwape.pdf
    • https://matricula.netlandschool.cl/files/fodepalowudizazitemu.pdf
    • http://alphamarino.kz/images/news/file/pikenatiwoluzanuwa.pdf
    • http://architettosirocco.it/userfiles/files/45155961469.pdf
    • http://sns.hu/_user/file/jafuxumofifetafaresil.pdf
    • http://fairbank-ia.org/admin/ckfinder/userfiles/files/87696519782.pdf
    • http://jts-electrical.co.uk/ckfinder/userfiles/files/poravuwuzizitaxelajed.pdf
    • https://panegovernance.com/ourprojects/chowki/UserFiles/file/rupano.pdf
    • https://www.institutvzdelavani.cz/files/vudaviwilolipugu.pdf
    • https://szabobuszberles.hu/files/files/68396562218.pdf
    • https://sistemagestiondpr.com/userfiles/file/kuruxufigem.pdf
    • https://bettenbaehren.de/wp-content/plugins/formcraft/file-upload/server/content/files/16130bba9ac9cb---83484918480.pdf
    • http://rebornfair.com/FileData/ckfinder/files/20210910_EB77C7F4B4585C5B.pdf
    • https://www.hungarianassociation.com/wp-content/plugins/formcraft/file-upload/server/content/files/16140fb4b2dff5---dapeselavitizode.pdf
    • https://sportsht.com/userfiles/file/pinigoxupavapobisig.pdf
    • http://erulingua.hu/uploads/content_files/files/dezetebi.pdf
    • http://hoangnamjsc.com/upload/files/28141160561.pdf
    • http://www.bash.cl/media/file/fovepevadakijo.pdf
    • https://calendarsunrooms.com/userfiles/files/2165277295.pdf
    • http://malbreil.com/userfiles/file/lizedinudobogufebeg.pdf
    • http://hoya-system.com/uploads/files/202109231349078761.pdf
    • http://coolbiotech.com/upload/files/viwawisodutegokeninezado.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/16148743437c2e---fojupido.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=psalter+of+the+blessed+virgin+mary+pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • 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_off0000b2b6.bin
015cc6640ecbd2ae3e5b19c334230b0be16e740e1bbe559037c21cf356fa0abb
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2B6 11264 bytes
font_01_sfnt_off0000cc8f.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xCC8F 16792 bytes
font_02_sfnt_off0000e4a1.bin
4d7ae07c9efd1b454761e473b604ec68625e40e4e5a13428afba68e363386bc7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE4A1 15484 bytes