Malicious PDF — malware analysis report

Static analysis result for SHA-256 b10da7bf75ec2fbe…

MALICIOUS

PDF

89.9 KB Created: 2021-09-24 10:53:56 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 72f408d500c8e4bd59602ebabc433be8 SHA-1: 809e93376cdebfee52d7a818b7aad91fb8634706 SHA-256: b10da7bf75ec2fbe348e7cadf44c4896a8c307839d12943c737db331bd622f91
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It contains numerous embedded URLs, many pointing to compromised CMS uploads and disposable hosting, suggesting a link farm or redirection mechanism. The presence of an IP address literal in a URI further supports a suspicious network interaction pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9905

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://bulgankhangai.mn/userfiles/files/21584889559.pdf
    • https://www.koreayokogawa.com/ckfinder/userfiles/files/41275553508.pdf
    • https://xtremefitness.com.au/application/third_party/ckfinder/userfiles/files/gedijebenudekixaja.pdf
    • http://eros-arena-reutlingen.de/eros/userfiles/file/lojedukejuxev.pdf
    • http://acudrved.com/ckfinder/userfiles/files/53718960439.pdf
    • http://househouse.it/userfiles/files/konewol.pdf
    • https://hazeloyun.com/calisma2/files/uploads/baguwezikuradiwekel.pdf
    • https://www.asoriofrio.org/ckfinder/userfiles/files/figamiwaxojisolerekumur.pdf
    • http://ouhkpthaa.org/userfiles/84865889103.pdf
    • https://essuances.com/ckfinder/userfiles/files/49354899745.pdf
    • http://gelikonline.ru/content/Files/terexefowekug.pdf
    • http://211.129.1.225/system/ckfinder/userfiles/files/79065627793.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/b05f72ae0b25fb08f92d86f7b1ce59ee/3280535252.pdf
    • http://www.elmundodelapiscina.com/ckfinder/userfiles/files/71574480482.pdf
    • https://www.frontiermea.com/sites/all/libraries/ckfinder/userfiles/files/dekezitejewikuw.pdf
    • http://pro-group.ru/userfiles/files/62156094661.pdf
    • http://captainkillmite.com/uploads/files/202109070151211788.pdf
    • https://burragebrothers.com/demo/jolie/beta/userfiles/files/80735649128.pdf
    • http://erfansari.ir/ckeditor/files/files/kuzin.pdf
    • http://konberdbio.com/upload/files/wasejarafeviveloluritopu.pdf
    • http://dangkyidol.com/wp-content/plugins/super-forms/uploads/php/files/n2ktcphtv2gip670pu1bmiqvii/borofowetegetudu.pdf
    • https://mikludava.lt/images/files/68664448064.pdf
    • http://www.colegiometa.net/home/wp-content/plugins/formcraft/file-upload/server/content/files/1613fdc687ccca---torazegazonalama.pdf
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/82b71i0qsspa1vtrks5ot2ac9b/zudinesosixezas.pdf
    • https://jungleflightchiangmai.com/Uploads/files/tovefigof.pdf
    • https://spherule.org/wp-content/plugins/super-forms/uploads/php/files/16d3far2fhrnad1k1beln0tha2/42545285976.pdf
    • http://cw-cut.com/uploads/file/50818703416.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/ngfLrbzwjls/uplcv?utm_term=most+common+phrasal+verbs+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_off0000f850.bin
bf17d838e3e177af61b2bf7d69e9b0166c023ee222e68dbbf043d7e209b195e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF850 18940 bytes
font_01_sfnt_off00012828.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12828 16792 bytes
font_02_sfnt_off0001403f.bin
9a4673e92325e6164a2a51b12ddfdf31de28355c84faac47537f2dc4dcbaf688
pdf-font-stream PDF embedded font (sfnt) at offset 0x1403F 10992 bytes