Malicious PDF — malware analysis report

Static analysis result for SHA-256 c162e61bb1b9923f…

MALICIOUS

PDF

69.9 KB Created: 2021-09-27 06:46:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 7b6ba061a86373deb65ba67db61dd380 SHA-1: 4b92a4947a2de9f18a3480ca9f2e54dfa953eed1 SHA-256: c162e61bb1b9923f5c396ee8bf94e7432d14ced2141a6e3940c73675631465d1
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains identified as disposable hosting or compromised CMS uploads. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware distribution through these links. The document body is unreadable, but the heuristic firings clearly point to a link farm designed to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9837

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://offerseir.com/basefile/offerseircom/files/fomizid.pdf
    • http://kcntanduc.vn/img_duhoc/files/novoxerurojenefovirufi.pdf
    • http://cesarrodarte.com/userfiles/file/togakuzomex.pdf
    • http://hydrem.ru/images/file/lavepizidewoketi.pdf
    • https://dla-pracownika.pl/pliki_user/File/subofetesorij.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161424e3a430b2---mesapetem.pdf
    • http://ippinnudon.com/uploads/files/tazuridosafebidiguk.pdf
    • http://anthonyvienna.com/sites/default/files/file/18428079969.pdf
    • http://abwingsjanaf.com/uploads/files/15553793752.pdf
    • http://iscyber.com/userfiles/files/nujixebidexakulazali.pdf
    • http://www.unidacardoso.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614222b23d101---63337750471.pdf
    • https://suprizpin.com/calisma2/files/uploads/17479619300.pdf
    • http://rulada.by/upload/editor/files/18047386717.pdf
    • https://milorem-service.ru/userfiles/file/54136889742.pdf
    • http://teresachild.com/upload/files/81837216046.pdf
    • http://tikatalog.sk/_files/file/79128834874.pdf
    • http://kartelabasligi.com/images_upload/files/xukemebabamomaxewemel.pdf
    • https://radio-clipa.ro/userfiles/file/vokimefeverikosapofel.pdf
    • https://ski-valloire.com/ckfinder/userfiles/files/30886333537.pdf
    • http://ahkjt.com/upfile/file/keganogokosawatawofibaw.pdf
    • http://www.ktgroup.co.uk/ckfinder/userfiles/files/7831990935.pdf
    • https://www.gurkhasfinance.com.np/ckfinder/userfiles/files/77724242429.pdf
    • http://hiroshima-teishaku.com/userfiles/file/72848664556.pdf
    • http://nwatchonline.com/userfiles/file/zubedilazagezerim.pdf
    • https://biorenta.lt/ckfinder/userfiles/files/3921012872.pdf
    • http://perfectionistpaintingnj.com/ckfinder/userfiles/files/koporu.pdf
    • https://infravoip.com/wp-content/plugins/super-forms/uploads/php/files/30244ba2577620be255c8007c556811c/94564145439.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=how+to+make+a+live+photo+a+background
    • 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_off0000b1a2.bin
6af7a709f326445d16fd257e7138d0d405bd8103c4dfce104e58ff1e62cd86aa
pdf-font-stream PDF embedded font (sfnt) at offset 0xB1A2 15380 bytes
font_01_sfnt_off0000d838.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xD838 16792 bytes
font_02_sfnt_off0000f04f.bin
79ed2d6b848d1466448d7d2fa8380391c7f9e99b92a4ddec68896853827130cb
pdf-font-stream PDF embedded font (sfnt) at offset 0xF04F 11268 bytes