Malicious PDF — malware analysis report

Static analysis result for SHA-256 90e384f587670218…

MALICIOUS

PDF

87.9 KB Created: 2021-07-27 06:20:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f9f443577f436b2a883a680da85d2ed6 SHA-1: 7f96b2aef38e9852b9a895410a0c534baa42035f SHA-256: 90e384f5876702188b79205007d3c73f95bd4aeb20158c0f4cf0fe1853275617
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample was detected by ClamAV as Pdf.Phishing.Trojan and flagged by an ML classifier, indicating malicious intent. It contains numerous external links, many pointing to compromised WordPress sites or disposable hosting, suggesting a link farm used for phishing or malware distribution. The presence of PDF_SEO_DISPOSABLE_LINK_FARM and PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM heuristics further supports this. Although no scripts were explicitly extracted, the PDF structure and link farm behavior are indicative of a malicious document designed to redirect users to potentially harmful content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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://anhuizhkj.com/upload_fck/file/2021-7-23/20210723074418972086.pdf
    • https://ka-base.no/images_content/file/ledosulap.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ce957588247---49590073360.pdf
    • https://cruiseship.cruises/wp-content/plugins/super-forms/uploads/php/files/vtl92iqaaoh6vdhua66n3er3fh/31343625613.pdf
    • http://ominocoibaffi.it/userfiles/files/naminoritaxalijulovapaj.pdf
    • https://www.c2commercial.com/wp-content/plugins/super-forms/uploads/php/files/c22d155619732854723343abd3d32047/mojuxotezo.pdf
    • https://legacyltg.com/wp-content/plugins/super-forms/uploads/php/files/7c844a6dfb26b16e3f5a237ca6b93d43/zakanolope.pdf
    • https://www.arc-welding.co.uk/wp-content/plugins/super-forms/uploads/php/files/4lt5if18uq85ssplk4u8u1meef/11655102790.pdf
    • https://impactcleaningserviceskc.com/wp-content/plugins/super-forms/uploads/php/files/368124fac84d6ffd2adfe58ca2fdd63b/4495358994.pdf
    • https://vokalensemble-vocembalo.ch/userfiles/file/xetebisusanag.pdf
    • https://thejinglelab.com/wp-content/plugins/super-forms/uploads/php/files/el7hlnr2h1suptehcnrehacqre/24093839283.pdf
    • http://benardoutlite.com/admin/fckeditor/fckdata/file/24730519666.pdf
    • https://www.gsccn.it/wp-content/plugins/formcraft/file-upload/server/content/files/16098d5eee24ef---bitafebinojekorirekomegu.pdf
    • http://www.expo-hotel.com/english/wp-content/plugins/formcraft/file-upload/server/content/files/160d8e6ff551b6---gimujofalunisetilomom.pdf
    • https://paperland.bg/uploads/file/80089415622.pdf
    • https://dreamscapes.ca/dream_scapes/userfiles/files/80484333716.pdf
    • http://nowator-zpu.pl/userfiles/file/kabezufuwisuvotunixi.pdf
    • http://ddgasul.com/userfiles/file/fotave.pdf
    • https://maintogelonline2.org/contents//files/pisovizuzigukafegimedezo.pdf
    • http://www.sphotobooth.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606f305b246ae---texetisu.pdf
    • http://pulsrmedia.com/wp-content/plugins/formcraft/file-upload/server/content/files/160893fae83fc7---muwixipakumubalijapuvuf.pdf
    • https://daiichigroup.net/uploads/news_file/7364092925.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=recetas+de+comida+mexicana+facil+rapida+y+economica+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_off0000f231.bin
c7cb858c351c1657a1b7559ecb7d0e068e6de9d7fa30b360caefa7af7650bfaa
pdf-font-stream PDF embedded font (sfnt) at offset 0xF231 17424 bytes
font_01_sfnt_off00011e8b.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11E8B 16792 bytes
font_02_sfnt_off000136a2.bin
9f766cc4040673980456d689090e39a2dbd6e03fd8b7bd210ddcc54b2d58cbec
pdf-font-stream PDF embedded font (sfnt) at offset 0x136A2 11040 bytes