Malicious PDF — malware analysis report

Static analysis result for SHA-256 1d4e23303459d5c2…

MALICIOUS

PDF

73.1 KB Created: 2021-09-03 16:27:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 67ba8a4ffee80bc5242bca71b024e825 SHA-1: 50ae7ad8564bc34dc684ba50c50718ad1f397dee SHA-256: 1d4e23303459d5c24ec9d3401f63ec29c9cb43bde0127149f90e3ad20148e15b
156 Risk Score

Malware Insights

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

This PDF file was flagged by multiple heuristics as malicious, including a high-confidence ML classifier and ClamAV detection as a phishing trojan. It contains a link farm pointing to numerous disposable domains and compromised CMS uploads, suggesting an attempt to distribute malware or conduct phishing. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, lacking readable content to infer a specific lure.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9956

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 https://www.adcgrain.com/wp-content/plugins/super-forms/uploads/php/files/4067d369d159dff741d64265e710d0f3/22722085268.pdf
    • http://galenbio.com/images/upload/file/85881645682.pdf
    • https://xn--p3t29jo1ed4o4xw.tw/upload/files/31667089968.pdf
    • https://menokatea.com/ckfinder/userfiles/files/79484100466.pdf
    • https://monarchwinemerchants.com/wp-content/plugins/super-forms/uploads/php/files/306c9589a13dc64a27686af739f244c4/lomasufegoxi.pdf
    • http://studiofranzoni.eu/userfiles/files/fubuxemetojov.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a5bba5bb74---65220635036.pdf
    • http://cargo3030.ru/wp-content/plugins/formcraft/file-upload/server/content/files/160a272e65e728---69920193404.pdf
    • http://houselandia.ru/files/kafuvelarixavuvukib.pdf
    • https://playerpress.com/ckfinder/userfiles/files/tofejodoralokilufobasax.pdf
    • http://nowyhotelik.pl/userfiles/file/61805637525.pdf
    • http://cgt-fo-csc.fr/wp-content/plugins/formcraft/file-upload/server/content/files/160a05880bc115---73514618153.pdf
    • https://evergreencans.com/userfiles/file/406753429.pdf
    • http://union.travel/ckfinder/userfiles/files/1661706121.pdf
    • https://smobiil.eu/userfiles/files/tefazoputo.pdf
    • http://se-ty.ru/uploads/userfiles/file/xefomovofapuv.pdf
    • http://cfacgroup.com/uploads/FCK_files/file/wiwuligizutidekubuzuler.pdf
    • https://parc-hotel.info/file/50690159055.pdf
    • http://archidaldegan.eu/userfiles/files/73854060612.pdf
    • https://rosycaffe.com/file/lanukuvinunazudoxevunibab.pdf
    • http://smartmedicaleg.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609b971f0d227---vopepopavuvelejuze.pdf
    • http://peak-experience-europe.com/images/blog/file/mifofaxe.pdf
    • https://art-lamps-rali.eu/files/file/geluxudifapev.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/zMnd8XtcwSM/uplcv?utm_term=adobe+pdf+reader+apk+android+2.3
    • 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_off0000bc56.bin
4580f7a056a13354a1f76ba81018a9a88332718deec086699bdfbc63d63fa484
pdf-font-stream PDF embedded font (sfnt) at offset 0xBC56 16376 bytes
font_01_sfnt_off0000e659.bin
0cc4ad9cf05934f8c6acf43b43da0c521e42edcf76b5bda2562f9c636fe2a198
pdf-font-stream PDF embedded font (sfnt) at offset 0xE659 10748 bytes
font_02_sfnt_off0000ff02.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF02 16792 bytes