Malicious PDF — malware analysis report

Static analysis result for SHA-256 c6a5897babe156ce…

MALICIOUS

PDF

83.5 KB Created: 2021-07-12 17:18:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 701f86b64970b260c1b5a412dd4d00a4 SHA-1: 80f9edf8ea56504342db1b15f16d3b7caea8c9ca SHA-256: c6a5897babe156ce1ab56e701956016a9f58e12646d522000309da28cd8126c1
192 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF containing embedded JavaScript, flagged by ML classifiers and ClamAV as malicious. Heuristics indicate it functions as a link farm, pointing to compromised WordPress sites, and employs lures related to invoices and callback phishing. The embedded JavaScript likely serves to download and execute a second-stage payload from one of the provided URLs.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 9

  • 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.
  • Callback phishing phone lure medium SE_CALLBACK_LURE
    Document asks the user to call a phone number in billing, refund, subscription, fraud, or security context — consistent with callback phishing or tech-support scam patterns. Suppressed for legitimate-issuer (IRS/gov/official-form) documents that carry no urgency or charge/dispute escalation.
  • 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.
  • Fake invoice / payment lure low SE_INVOICE_LURE
    Document contains invoice or payment language paired with an action verb — useful context when combined with link, macro, or attachment indicators
  • 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://frasertechno.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bfc24346a52---suxawiserinoviw.pdf
    • http://adhdadvisory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a216b168161---58778906631.pdf
    • http://hnkingdee.cn/Files/file/202163161525.pdf
    • https://readxyz.org/wp-content/plugins/super-forms/uploads/php/files/008c7fbbbc1f5b8b6cb7a7d2082ee6cf/21466458614.pdf
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6ee01676b---vitozu.pdf
    • http://futurepoolandspa.com/ckfinder/userfiles/files/bezowenuteba.pdf
    • http://proxima-design.cz/files/file/wadajiwazogedokat.pdf
    • https://realimpacto.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160a33a49ee05b---pomevokupu.pdf
    • http://aeskulap24h.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a8864b63878---rezenoviniteluparawiguj.pdf
    • http://boothbayharborshipyard.com/userfiles/file/52993135540.pdf
    • https://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/6dcb42f60e9e8b1a285bae7e168c0754/66431107545.pdf
    • http://nw-line.ru/generic/uploaded/59234233862.pdf
    • https://nowackleverkusen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1609c0d4dc9ed8---zawutanarakuta.pdf
    • https://jollytime.ru/wp-content/plugins/super-forms/uploads/php/files/1f1fa5d5f9c8c9ede840d8836cf8e110/fujekoregikekeji.pdf
    • https://www.rath-catering.de/wp-content/plugins/formcraft/file-upload/server/content/files/160783a9062068---42100294501.pdf
    • https://www.stamfordtaxis.com/wp-content/plugins/super-forms/uploads/php/files/ekdbaiiu1ko86lu8uf99i8nser/5904801751.pdf
    • https://werbemittelag.chupload/file/20819982382.pdf
    • https://gulertrafik.com/wp-content/plugins/super-forms/uploads/php/files/oto7s7e29iinoa4r0fadd2to5u/17958973474.pdf
    • https://my-natural-style.net/upload/files/letiba.pdf
    • http://clearspace-design.com/CKEdit/upload/files/zekizuvedapo.pdf
    • https://xn--78-6kce7dfhb9dwb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/98e26c7fbba3a09a39cb98b1c60200df/sowimanes.pdf
    • https://silatur.com/js/ckfinder/userfiles/files/tuxazefemapujakujadati.pdf
    • http://bsbcarpet.com/userfiles/file/19772937021.pdf
    • https://www.mixedclass.com.au/wp-content/plugins/super-forms/uploads/php/files/rbmn31o209khe9sapdqjovdamc/vutuzizosajavo.pdf
    • https://jewfri.kr/files/image/files/33573472756.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=account+notes+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_off0000e49e.bin
191c1dc7a6c9d1cfd5ee360ba377ba6a026a34e130380b04a22577bf01a4fb97
pdf-font-stream PDF embedded font (sfnt) at offset 0xE49E 10292 bytes
font_01_sfnt_off0000fbfc.bin
50bf42f65a5329ae3b1f7ecea5fa159016b21d967e36721d3447b7551ee0f8e8
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBFC 17076 bytes
font_02_sfnt_off000128c3.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x128C3 16792 bytes