Malicious PDF — malware analysis report

Static analysis result for SHA-256 23ea2374210fd9a0…

MALICIOUS

PDF

87.3 KB Created: 2021-06-28 10:51:31 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-14
MD5: a6ccbcbc04d232bf128f22a946681d0e SHA-1: b1395037d560902c94ab8c71b44b1322a1a7e4cb SHA-256: 23ea2374210fd9a099909e0d06a83526d755bfe9d75b2ca54f9114e675981df6
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. Heuristics identified it as a PDF link farm, with many URLs pointing to compromised CMS uploads or disposable hosting, suggesting a phishing or malware distribution scheme. The document body was unreadable, but the presence of numerous external links strongly supports the link farm attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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 http://baigeleather.com/userfiles/file/43645840822.pdf In PDF document text
    • http://hoanggiaphatland.com/uploads/image/files/53710294647.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606d8ef25b07e---68239144118.pdfIn PDF document text
    • http://plusbateria.com/wp-content/plugins/formcraft/file-upload/server/content/files/16071fe0b552bb---gosut.pdfIn PDF document text
    • http://cephedanismani.com/images/pages/file/vuzekiwirelede.pdfIn PDF document text
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a68b77c2ef0---35363334764.pdfIn PDF document text
    • https://upbilbao.com/ckfinder/userfiles/files/diwakinupuf.pdfIn PDF document text
    • http://www.ncstarim.com.tr/wp-content/plugins/super-forms/uploads/php/files/2bl644b3gs70foeuacr9kmpb67/21313827631.pdfIn PDF document text
    • https://kindliving.org/wp-content/plugins/super-forms/uploads/php/files/tmp/64077687423.pdfIn PDF document text
    • http://stromzeleny.cz/file/48374350829.pdfIn PDF document text
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160d9440600606---79542643498.pdfIn PDF document text
    • https://globalazeri.az/wp-content/plugins/super-forms/uploads/php/files/ug1dgnkg2osei7ckg91fhhsed4/26214888791.pdfIn PDF document text
    • http://scarpatti.com/files/komitinonizonoporil.pdfIn PDF document text
    • https://repare-ton-smartphone.com/userfiles/file/16961819754.pdfIn PDF document text
    • https://www.yoursurveysurveyors.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16089e1e8b055e---17279781788.pdfIn PDF document text
    • http://eduomania.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a6ff7987d58---xokugaxuv.pdfIn PDF document text
    • http://andreevmag.com/wp-content/plugins/super-forms/uploads/php/files/6ffc023df8fa5cc5fe85f6f135dd51fb/68555001674.pdfIn PDF document text
    • http://bet-balance.com/userfiles/file/duzamisinutitisixisi.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c198973ffd4---ratetesupobumanekokip.pdfIn PDF document text
    • http://nakakinpump.kr/fckeditor/upload/file/mutudiwilosivopabisag.pdfIn PDF document text
    • https://alperbehang.nl/userfiles/file/87014129618.pdfIn PDF document text
    • http://zeguvietnam.com/uploads/ckfinder/files/vexuvanezefudupodujas.pdfIn PDF document text
    • https://greyquotient.com/wp-content/plugins/super-forms/uploads/php/files/5e86e5b6a32a48af5fe530680a9eecdd/gixolujafedo.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/fzgW7-mxBc0/uplcv?utm_term=after+effects+2020+shortcuts+pdfPDF link annotation
    • 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_off0000f242.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF242 17192 bytes
SHA-256: 93cbf3f4963673fb3ad1f4752bb7751bd3756c3db25d70f9a348cb7f713b8f0a
font_01_sfnt_off00011f26.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11F26 10636 bytes
SHA-256: 2c347daabb972054d39ad64f3aa31f4197973ba244467e44d20674919bc27d75
font_02_sfnt_off000137b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x137B4 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1