Malicious PDF — malware analysis report

Static analysis result for SHA-256 8916dbb1fafa6681…

MALICIOUS

PDF

98.9 KB Created: 2021-06-30 12:00:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e90552bbefb74563fcf1ae55508dedf9 SHA-1: a1e0844fe04ff8b8cc39c017d6c5a36954033e17 SHA-256: 8916dbb1fafa6681e2f289790cb9be582aaf2945a6b3adbe15fbe34172dd5fa4
196 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1553.004 Mark-of-the-Web Bypass T1203 Exploitation for Client Execution

This PDF was flagged by ClamAV as a phishing trojan. The heuristics indicate it contains a link farm pointing to compromised WordPress sites, likely for hosting malicious content. Crucially, the document contains instructions to disable security software, a strong indicator of malicious intent to bypass defenses and download further payloads.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9800

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • Security software disable instruction high SE_SECURITY_BYPASS
    Document instructs the user to disable antivirus or security software — unusual for ordinary documents and high-risk in an unsolicited file
  • 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://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a7372421d3d---pivimolozewid.pdf
    • https://www.gasserbush.com/wp-content/plugins/super-forms/uploads/php/files/db766240ba2ab511b1ea0e4357abe1a6/42121720830.pdf
    • http://www.gradur.ba/wp-content/plugins/formcraft/file-upload/server/content/files/160819c1d2d2b6---97175366145.pdf
    • http://neodentpetrosino.it/userfiles/files/mamukituboli.pdf
    • https://amalighting.com/wp-content/plugins/super-forms/uploads/php/files/550c2ddc6621f29ef55b698a59a6f763/89719357753.pdf
    • http://willtorock.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac168da5cb8---rubodeduvorodonaxo.pdf
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/f386dcb8fd6d28ff23a7edce98be3d21/33403327853.pdf
    • http://tvoirostov.ru/ckfinder/userfiles/files/desip.pdf
    • http://aqbnb.com/uploadfile/file/61387902283.pdf
    • http://festivaldeliteraturadepereira.com/wp-content/plugins/formcraft/file-upload/server/content/files/16080ef519850a---80934235185.pdf
    • http://osullivanspressurewashing.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607ba713da974---72614553531.pdf
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/bciuds3gscofhbvhqln1b6jutf/95201986110.pdf
    • http://menafundinfo.com/userfiles/file/duzabiteladi.pdf
    • http://zabradli-znerezu.cz/userfiles/file/90818094858.pdf
    • http://vizesblokk.hu/files/file/20074527636.pdf
    • http://accessiblevehicleservices.com/userfiles/file/93062860187.pdf
    • http://alemotta.com/resources/original/file/nowisekaju.pdf
    • https://www.davinci.dk/wp-content/plugins/formcraft/file-upload/server/content/files/160abe65aea875---34391821030.pdf
    • https://goodluckfishing.com/ckfinder/userfiles/files/8445645189.pdf
    • http://branpc.in/ckfinder/userfiles/files/34724609755.pdf
    • http://philippinesroadshow.com/wp-content/plugins/super-forms/uploads/php/files/da11f1a8a1180ee671e9d8040f3c2a9e/wosekokuxuxomiw.pdf
    • http://jockmurray.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609307f24bacd---6373072056.pdf
    • http://montaze.org/democms/userfiles/file/vadejavovevuri.pdf
    • https://aimara-bg.com/userfiles/file/54203127695.pdf
    • https://gw21.ch/uploads/userfiles/file/ropefarulidapaz.pdf
    • http://classicalgardenstatues.com/uplds/file/vojejotiguxiboxotede.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=power+plant+engineering+interview+questions+and+answers
    • 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_off00011da0.bin
04e2d7f94e4c3fe8d59dcb1fe2e3ccd9da97180554cb0f55f2844595bec3c8fa
pdf-font-stream PDF embedded font (sfnt) at offset 0x11DA0 17800 bytes
font_01_sfnt_off00014c69.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x14C69 16792 bytes
font_02_sfnt_off00016480.bin
4c2e966738b7efc3ac484ffa3d22a3f8db6d4f54e08507c208fa5c3818123704
pdf-font-stream PDF embedded font (sfnt) at offset 0x16480 10964 bytes