Malicious PDF — malware analysis report

Static analysis result for SHA-256 c94d31d6eec76417…

MALICIOUS

PDF

69.8 KB Created: 2021-10-03 11:44:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 6337ec865a1a2dd92dd1837441109eca SHA-1: e2d54aaeeca52617df4303e22b4b75fc0d3bc602 SHA-256: c94d31d6eec76417ae2236a1f9de46dad76458cf8132a376b0f30fb8db287544
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF was flagged by ClamAV as a phishing trojan and ML classifier indicated high maliciousness. Heuristics indicate the PDF functions as a link farm, redirecting users to various external URLs, some hosted on compromised WordPress sites. The presence of embedded URLs and the nature of the heuristics strongly suggest a phishing or credential harvesting attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9975

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://catamma.ru/uplcv?utm_term=i+get+up+in+spanish
    • https://senfina.top/uploads/files/rosewadeko.pdf
    • http://chamdure.com/DATA/files/25804458218.pdf
    • http://vagtteam.dk/userfiles/Files/10724183051.pdf
    • http://www.cargeacrew.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/16136b3005d2da---lulatabupanuvativowosule.pdf
    • http://aburobocon2019.mnb.mn/uploads/files/15036043595.pdf
    • http://vietsaovang.com/uploads/userfiles/file/zofatidajejabelu.pdf
    • https://stichtingech.org/ckfinder/userfiles/files/vidatezedotile.pdf
    • http://immobilieninvestors.de/userfiles/file/mukiput.pdf
    • https://beauty-full.ru/uploads/files/tatotusimeruviva.pdf
    • http://stefanourso.com/public/userfiles/file/gomezuzapasawamawarikaked.pdf
    • http://recviem.ru/img/upload/70558786971.pdf
    • https://netiko.ge/img/Data/file/67355605715.pdf
    • http://italianopizzeria-pg.com/uploads/files/69753682752.pdf
    • http://www.andreapondika.cz/file/xiwove.pdf
    • http://artmetinc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1612f15aeb568a---7322067805.pdf
    • https://intelean.com/wp-content/plugins/formcraft/file-upload/server/content/files/161387d5079330---24404801888.pdf
    • http://le383.com/uploads/files/66108600488.pdf
    • https://majorsagilekvaros.hu/uploads/file/31358110563.pdf
    • http://robbes.nl/media/files/62042935325.pdf
    • http://munsusa.org/userfiles/file/20210905003012.pdf
    • http://jjw-led.com/userfiles/file/meguzogiwirovumafil.pdf
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/161493e74d21b6---nexopajuren.pdf
    • https://intervalhousehamilton.org/ckfinder/userfiles/files/63333616357.pdf
    • http://africalegal.nl/userfiles/file/rovotabumajoninazutege.pdf
    • https://www.spitalmoldovanoua.ro/ckfinder/userfiles/files/59865752530.pdf
    • 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_off0000b2b0.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xB2B0 16792 bytes
font_01_sfnt_off0000cac2.bin
8601e3a9c2f7a0c2da3a092e9c85d4e7c2f4c5082fa7a49c4ec85f7eb2436c86
pdf-font-stream PDF embedded font (sfnt) at offset 0xCAC2 15748 bytes
font_02_sfnt_off0000f250.bin
18f713f558ebd8d0d9ced33e318c7964d7c71f91914d31b57654da6dee3f08ed
pdf-font-stream PDF embedded font (sfnt) at offset 0xF250 10316 bytes