Malicious PDF — malware analysis report

Static analysis result for SHA-256 54edfd71cc7281d5…

MALICIOUS

PDF

70.8 KB Created: 2021-09-27 06:50:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-11-24
MD5: 10206e6fae8cb05dfe84f73270544070 SHA-1: c4890ecd583efe00cff7e251f01c1d7ca1a75994 SHA-256: 54edfd71cc7281d59b5e714c7567e9b968e04a40ada234914a7ce46647bde7bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was flagged by ML classifiers and ClamAV as malicious, specifically as a phishing trojan. It contains numerous embedded URLs pointing to compromised WordPress sites and other disposable hosting, suggesting a link farm designed to redirect users to malicious content. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, indicating it's not intended for direct user reading but rather as a container for malicious links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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://garglob.ru/uplcv?utm_term=latin+words+beginning+with+a PDF link annotation
    • https://trucraftsmanship.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143a98425e6a---xesizagepefanebux.pdfIn PDF document text
    • http://italy-ex.com/images/blog/file/26802283486.pdfIn PDF document text
    • https://www.urban-quartz.co.uk/wp-content/plugins/super-forms/uploads/php/files/4d6d3729537fb0d8b8670b68f5f1d5b6/43793605253.pdfIn PDF document text
    • http://grupposcorcia.it/userfiles/files/rekegemiparol.pdfIn PDF document text
    • https://tourgardan.com/basefile/tourgardancom/files/mezotekelonapuwasabak.pdfIn PDF document text
    • http://magicfood-cn.com/files/20210925035016.pdfIn PDF document text
    • http://mwcapital.net/ckfinder/userfiles/files/79075586439.pdfIn PDF document text
    • https://bloomeng.com/uploads/gugebivopaxipul.pdfIn PDF document text
    • http://creationart.hu/files/file/62117032740.pdfIn PDF document text
    • http://tridiart.cl/ckfinder/userfiles/files/gonar.pdfIn PDF document text
    • http://trenermichal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161366f74d06e2---39282210805.pdfIn PDF document text
    • http://denetimmusavirlik.com/userfiles/file/fikosomogujepanepefofo.pdfIn PDF document text
    • http://autoscuolepintozzi.it/userfiles/files/jezedojarigikinog.pdfIn PDF document text
    • http://scherzerpc.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vosanugirija.pdfIn PDF document text
    • http://capitaldanceacademy.com/userfiles/files/rakuz.pdfIn PDF document text
    • http://zgic.ru/!upload/files/xakowavifule.pdfIn PDF document text
    • https://x-software.cz/data/file/tibojizavarafijevi.pdfIn PDF document text
    • https://championsforchildren.org/wp-content/plugins/super-forms/uploads/php/files/62e0888505d5301c11aaad205d62862c/ronekowosi.pdfIn PDF document text
    • http://dr-onesrl.com/userfiles/files/19462290231.pdfIn PDF document text
    • https://honkakuji.jp/honkakuji/images/ckfinder/files/zumakubovenekafejeted.pdfIn PDF document text
    • https://gamepinleri.net/calisma2/files/uploads/xerolagerebapojebal.pdfIn PDF document text
    • http://louisamerino.com/userfiles/file/9533815847.pdfIn PDF document text
    • http://windmill-bv.com/userfiles/files/musumor.pdfIn PDF document text
    • https://granitabrasive.hu/editor_up/24393956720.pdfIn PDF document text
    • https://sikahaiphong.com/images/news/files/88605891911.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_off0000b236.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB236 16828 bytes
SHA-256: d3652d7ba33facede4011e1395a215fc716c6c9ccdb34242aef6954fd4c89da4
font_01_sfnt_off0000dd23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDD23 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000f53a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF53A 10664 bytes
SHA-256: a27f29c39e2e45713af269bd45b41bcbc0d95fb55b080bdce45361d95e89813d