Malicious PDF — malware analysis report

Static analysis result for SHA-256 7f656abff996cc95…

MALICIOUS

PDF

76.5 KB Created: 2021-09-14 09:37:15 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: bbbf225bdd61546c2d1d6a2ee467c0ec SHA-1: 70acd5a23f0809b3fbb92b20e328214c97993707 SHA-256: 7f656abff996cc95acb7b5a8a675cac29f89257350abe7ffe78a81a22c24994d
156 Risk Score

Malware Insights

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

The PDF was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, with numerous embedded URLs pointing to various domains, some of which are hosted on compromised CMS uploads or disposable hosting. While the document body is unreadable, the presence of multiple links and the detection as a phishing trojan strongly suggest a malicious intent to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9948

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 http://mh-gartengestaltung.de/userfiles/file/noxuva.pdf
    • https://giverny-bkk.com/upload/files/89252899530.pdf
    • http://redondoclassicburger.com/uploads/files/20707724015.pdf
    • https://semangkamerah.com/contents/files/junozuju.pdf
    • https://lisacutler.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613a9a331e0d7---40489684127.pdf
    • https://www.medicalbi.com/ckfinder/userfiles/files/karinemokuvesixiwaruj.pdf
    • http://beta-rc.com/upload/files/rowirevotosejo.pdf
    • https://rdw-wolf.de/backend/ckfinder/userfiles/files/biriduburuzimebujupakud.pdf
    • https://lokmangal.co.in/wp-content/plugins/super-forms/uploads/php/files/5f92365dc253384ade629af24cf1f804/36909316491.pdf
    • http://www.afamaresme.org/wp-content/plugins/formcraft/file-upload/server/content/files/1612f69a0ee597---94918601538.pdf
    • http://wwsm-hk.com/files/file/29551610105.pdf
    • http://ankaraeksioglu.com/resimler/files/52872336208.pdf
    • http://smartpaintingplus.com/userfiles/files/sewokojaza.pdf
    • http://www.sanruou.com/app/webroot/uploads/files/bojarunipiposutabur.pdf
    • http://tekizolasyon.com/ckfinder/userfiles/files/75444770909.pdf
    • http://www.uppld.org/wp-content/plugins/formcraft/file-upload/server/content/files/161377047ce35a---3613280426.pdf
    • http://hcm-invoice.vn/hinhanh_fckeditor/file/65603892099.pdf
    • http://dianacb.cz/userfiles/file/lipowusezofopunewaxixas.pdf
    • http://ltmetal.com/userfiles/files/14177341273.pdf
    • http://friluftsgruppen.se/wp-content/plugins/formcraft/file-upload/server/content/files/161363e4fc9f94---50280657709.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/1613573eda7e0f---kapagodagag.pdf
    • http://hurtmar.pl/Upload/file/luzebadugu.pdf
    • http://ucg-eg.com/userfiles/file/74160942246.pdf
    • http://hanasushi6.com/uploads/files/wapekujomutexevedirubar.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/DOqCt-cVA4I/uplcv?utm_term=turn+off+auto+software+update+android
    • 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_off0000c618.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xC618 16792 bytes
font_01_sfnt_off0000de2f.bin
8c603384b1c9e5b1972c8d843d171027a2e02ee86aa69838ddada7810b3ca911
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE2F 10596 bytes
font_02_sfnt_off0000f692.bin
c8bf3872e05ce0cf3ddb4fe66e5e1329d403c9f6cfcfb3105ee6dec6c689dd38
pdf-font-stream PDF embedded font (sfnt) at offset 0xF692 17996 bytes