Malicious PDF — malware analysis report

Static analysis result for SHA-256 de5694dd9534056f…

MALICIOUS

PDF

70.5 KB Created: 2021-09-08 20:00:12 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-12
MD5: 71c74d0db5a53d8d56b541eefc9b2738 SHA-1: 881503ae63010778f8d7d399b389304957213e70 SHA-256: de5694dd9534056f837ad92123bf4d011b4f80670d6bf896c97ad7580fff371a
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous links to external websites, many of which are hosted on compromised or disposable domains, suggesting a phishing or malware distribution campaign. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates a non-clustered link farm on disposable hosting, and 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' points to links on compromised WordPress sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or trojan delivery.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://oniceh.ru/uplcv?utm_term=job+interview+guidelines+pdf PDF link annotation
    • http://seoulmenu.com/uploads/files/89397180039.pdfIn PDF document text
    • http://ccsctda.com/ckfinder/userfiles/files/20210905_001247.pdfIn PDF document text
    • http://abhinavabhishad.org/userfiles/file/gavukenodivesi.pdfIn PDF document text
    • http://tce.vn/imagesflashupload/file/17656485144.pdfIn PDF document text
    • http://mexvp.com/ckfinder/userfiles/files/96936201931.pdfIn PDF document text
    • http://karinameal.com/imgdish/files/woxozu.pdfIn PDF document text
    • http://poultech.net/d/files/wedanepowasimakitas.pdfIn PDF document text
    • https://kubermatkaplay.com/ckfinder/userfiles/files/77840596970.pdfIn PDF document text
    • https://www.frontierexim.com/wp-content/plugins/super-forms/uploads/php/files/l7uim5a2thpce46to131df9vl0/88952294938.pdfIn PDF document text
    • http://indyztyle.com/ckfinder/userfiles/files/laruvufelagizideputuf.pdfIn PDF document text
    • http://eltdb.com/UserFiles/files/5028727652.pdfIn PDF document text
    • http://careerhack.net/wp-content/plugins/formcraft/file-upload/server/content/files/1612eb60bf2e53---menanonujuzen.pdfIn PDF document text
    • http://mirai-kankyo.com/userfiles/files/kasaguduw.pdfIn PDF document text
    • https://bvphcn.bdata.vn/upload/files/53623051935.pdfIn PDF document text
    • https://htchninc.com/d/files/gudorusisugokupe.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612edfec01c15---nexawajatagapipuxedotase.pdfIn PDF document text
    • https://asthasupermarket.com/userfiles/file/27078793759.pdfIn PDF document text
    • http://havefuntogether.com/image/upload/File/ludixikesafisikode.pdfIn PDF document text
    • https://supermagnum-bg.com/ckfinder/userfiles/files/45870722547.pdfIn PDF document text
    • http://zrdb-drogbud.pl/Upload/file/gimebigepuninadexa.pdfIn PDF document text
    • http://schokofontaenen.de/idata/72544989481.pdfIn PDF document text
    • https://5a.ro/ckfinder/userfiles/files/67055214687.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_off0000b23b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB23B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off0000ca4d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCA4D 16624 bytes
SHA-256: b60ae529a9eb33cad991b9df3d7e13cb6804a60845de47276c9d29f0598f3764
font_02_sfnt_off0000f363.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF363 10892 bytes
SHA-256: da7d3a3286e796055b3af8e1ecc8a6065901eb757e657ea83e5f0b20f5a7b7f3