Malicious PDF — malware analysis report

Static analysis result for SHA-256 d1343aaf32553630…

MALICIOUS

PDF

81.3 KB Created: 2021-09-02 23:00:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4f654cf0959ad3c606d0383f54979e1a SHA-1: 27f434bb88eff9fc85c0da8cb8cd2162fbd71db7 SHA-256: d1343aaf32553630ed9e94765b1b7d91742a7a9ef32ffeb59f00cfd604cd333a
164 Risk Score

Malware Insights

MITRE ATT&CK
T1059.007 JavaScript T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and numerous external links, many pointing to compromised CMS upload directories or disposable hosting. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware distribution. The embedded JavaScript is a common technique to redirect users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9960

Heuristics 7

  • 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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://nomylo.ru/uplcv?utm_term=free+maths+worksheets+for+grade+6+pdf
    • http://jlm-kg.com/uploads/file/22212722246.pdf
    • https://www.bouldersudbury.org/wp-content/plugins/formcraft/file-upload/server/content/files/160c15587736cf---mejogesuj.pdf
    • http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a84d293dbd6---levuwefatafubifotesuwo.pdf
    • http://drairtools.com/ckfinder/userfiles/files/94788594490.pdf
    • http://windcampus.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a5a38cad62---kupunejigogawonu.pdf
    • https://www.revistadefiesta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b22a67980a8---61076713965.pdf
    • https://parvazyab.com/basefile/api203/files/12887356036.pdf
    • https://chachachat.info/js/ckfinder/userfiles/files/puvis.pdf
    • https://remoteyourstaff.com/calisma2/files/uploads/padowitodezapuridoti.pdf
    • http://indiebookoftheday.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607eb3a82ff93---56655854556.pdf
    • http://fine-cottage.ru/userfiles/files/jegibavo.pdf
    • http://mpti.ru/userfiles/file/gotolopuwiroxeza.pdf
    • https://www.autodepotperformancegroup.ca/wp-content/plugins/super-forms/uploads/php/files/5t4jo7idhb9ko2chhqtsl2degj/wasefodaluvedelepapexowa.pdf
    • http://veganogle.es/uploads/ckfinder/files/37288531673.pdf
    • https://jaunimodienos.lt/wp-content/plugins/super-forms/uploads/php/files/n3sljhqmuouprvpl5f42hsi6jg/foweduzuk.pdf
    • http://jrpst.pl/userfiles/file/zowabunoreto.pdf
    • http://vtracauto.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607e33c41c62a---bevusubowezikev.pdf
    • http://pahsclassof2005.com/clients/d/d6/d61c4c031b0f3af13d3e88110ef3a3e1/File/72968692677.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/88532a3b9d38db01fdf1a235fa7f52cc/fiwotepofogalobap.pdf
    • http://sluchatka-shop.cz/files/upload/files/51086986737.pdf
    • https://amiablediamonds.com/wp-content/plugins/super-forms/uploads/php/files/dba10332ccd7dd6e03adeafd57d09652/87393604660.pdf
    • https://koetec.com/home/~ptow/public_html/ckfinder/userfiles/files/jodufepalisasu.pdf
    • http://moffatcountyhighschool65.com/clients/878592/File/papuvenalapob.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_off0000d991.bin
71261c03b3c1fc2cd92ed35b3ae22f307d7acb83bb17c722224aa8efbcb63465
pdf-font-stream PDF embedded font (sfnt) at offset 0xD991 11028 bytes
font_01_sfnt_off0000f320.bin
ff1288314ca6c62eb1a30814fdd33c2a3ca70e6748ca700c7d436870fa6a0468
pdf-font-stream PDF embedded font (sfnt) at offset 0xF320 17040 bytes
font_02_sfnt_off00011f8e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F8E 16792 bytes