Malicious PDF — malware analysis report

Static analysis result for SHA-256 f6839b8a0778ce3f…

MALICIOUS

PDF

89.0 KB Created: 2021-09-01 17:32:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-05
MD5: e385617974ef99d15152fbcd877226c9 SHA-1: b70dae37557cece8e341ff3e1132291bbc5025b1 SHA-256: f6839b8a0778ce3fb75476a634e8b72ba9521395ca141eff7d858d437422a3d6
176 Risk Score

Malware Insights

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

The PDF file was detected as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. It contains numerous embedded URLs pointing to various domains, many of which appear to be compromised WordPress sites or disposable hosting, suggesting a phishing or malware distribution campaign. The presence of multiple external URIs and link farms strongly supports this attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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 https://inwebjor.ru/uplcv?utm_term=bst+web+guide+manual PDF link annotation
    • https://aduanaldelvalle.com/userfiles/file/domomakinolilipajapexibo.pdfIn PDF document text
    • https://aliencosmicexpo.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c881257973---zovulatimawinorubawi.pdfIn PDF document text
    • http://www.hptindia.com/wp-content/plugins/formcraft/file-upload/server/content/files/1611705d8d53b6---jigukasokovobaz.pdfIn PDF document text
    • https://mudrun.com/home/mud/public_html/ckfinder/userfiles/files/68468335868.pdfIn PDF document text
    • https://faresaldabbous.com/uploads/files/jowigawotirubolefuxiwes.pdfIn PDF document text
    • http://cochemical.com/upload/files/2153247234.pdfIn PDF document text
    • https://fedico.ca/upload/editor/file/kanumaz.pdfIn PDF document text
    • http://kingspec.su/wp-content/plugins/super-forms/uploads/php/files/u4e12r9g0np5l5304sdl29lovc/tujonet.pdfIn PDF document text
    • http://traktorpulling.de/ablage/userfiles/files/14989524619.pdfIn PDF document text
    • https://www.frontieregypt.com/sites/all/libraries/ckfinder/userfiles/files/guviben.pdfIn PDF document text
    • https://fietenhaardenenkachels.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16084a9dfc7a70---fazivavanowemipobanabavul.pdfIn PDF document text
    • http://fd-health.com/upload/ckeditor/files/61366899505.pdfIn PDF document text
    • http://lhdrum.com/User_File/UpFile/file/20210603141015_NzgzNDkyOTYwMzY=.pdfIn PDF document text
    • http://nebovsem.ru/app/webroot/files/files/16159876713.pdfIn PDF document text
    • https://jbdclothiers.net/emailer/userfiles/file/43432194123.pdfIn PDF document text
    • https://siangyun.com/upfiles/editor/files/3061655993.pdfIn PDF document text
    • http://www.herbertvanderbrugghen.nl/draft/naxemixodivefulasuzut.pdfIn PDF document text
    • https://auf.vn/wp-content/plugins/super-forms/uploads/php/files/s8mvv54nmmsjrul676go2tutb3/vasitu.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/37490709609.pdfIn PDF document text
    • http://iphonedown.com/ckfinder/userfiles/files/63830703526.pdfIn PDF document text
    • https://www.mozartcantat.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16092626df1c89---kovuxadanifesuv.pdfIn PDF document text
    • http://wcsps.com.tw/ckfinder/userfiles/files/74890979314.pdfIn PDF document text
    • https://www.chinacimctrailer.com/wp-content/plugins/super-forms/uploads/php/files/3f6b2440c9bfc7af67f292fd1f7e6138/84089067269.pdfIn PDF document text
    • http://140.121.180.103/ckfinder/userfiles/files/xonugekijul.pdfPDF link annotation
    • 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_off0000f83f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF83F 17316 bytes
SHA-256: ee7cc569b5ceac141aa162134d8e39019ff2bdc2053d7262fd7a79b18ff8bc3c
font_01_sfnt_off00012608.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12608 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013e1f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13E1F 10752 bytes
SHA-256: c468edeeb91dd7e6e5b9ca649bbdb85ad102a0610d302e8715605f14dd99f504