Malicious PDF — malware analysis report

Static analysis result for SHA-256 d057a90bd1f9e89d…

MALICIOUS

PDF

68.6 KB Created: 2021-10-01 00:11:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c67ff8797e8ac28b3c7ed6ee7f3e8eed SHA-1: 7e55a2a5bd60ab659e0465dae8d2a0b471d38f76 SHA-256: d057a90bd1f9e89dacecfa59cb550c3c50d02f8aef288cf066eb6a09b3a47ad1
204 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The sample is a PDF document containing embedded JavaScript, which is a common technique for delivering malicious payloads. It includes numerous links to external websites, many of which are hosted on compromised CMS platforms or disposable domains, suggesting a phishing or malware distribution campaign. The ML classifier and ClamAV detection strongly indicate malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 8

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • 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.
  • 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.
  • 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://khmernative-rice.com/userfiles/file/69791710880.pdf
    • https://iieng.org/editor/ckfinder/userfiles/files/weleredurivef.pdf
    • https://stthomasorthodoxchurchsouthpampady.com/userfiles/file/64974308155.pdf
    • https://www.hs-hofgastein.salzburg.at/ckfinder/userfiles/files/34925562059.pdf
    • http://meuble-tunisie.com/userfiles/file/mukalunakevereboka.pdf
    • http://diennuocdanang.com/uploads/image/files/7222053669.pdf
    • http://osoboebludo.com/ckfinder/userfiles/files/gajar.pdf
    • http://misterholidaysanprisco.it/userfiles/files/82022806538.pdf
    • https://noithathoaphat11.com/upload/files/febevuborasiro.pdf
    • http://marleenjansen.nl/images/uploadfiles/66819891366.pdf
    • http://assessmentinsight.com/ckfinder/userfiles/files/41355582358.pdf
    • https://ltes.tw-goods.com/UserFiles/files/59163810716.pdf
    • http://ekhoron21.mn/uploads/files/dapozeradonokujuboj.pdf
    • http://hotspot-usa.com/js/upload/files/segev.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/e7b25f92bc805ac0e83104b56c0a3cb6/tebegakubu.pdf
    • http://imhome-listings.com/userfiles/files/bukunam.pdf
    • https://trystsalonri.com/images/file/92599134601.pdf
    • http://zubrcup.by/files/files/vapoduroxetipubeni.pdf
    • https://reformedgeneration.com/userfiles/file/57248809776.pdf
    • https://www.glasswindowequipment.com/wp-content/plugins/super-forms/uploads/php/files/0f8eb027b0f5e3492f5e1f42ae2347ea/22530113785.pdf
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614587d5432c9---2301361494.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/YTWXjIUwRh0/uplcv?utm_term=balloon+defence+6
    • 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_off0000ad18.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAD18 16792 bytes
font_01_sfnt_off0000c52f.bin
c78635e3bc436b32f3646f433b88f929260182ecb83a0be2ec272203ade18370
pdf-font-stream PDF embedded font (sfnt) at offset 0xC52F 10232 bytes
font_02_sfnt_off0000dc48.bin
189c5633c5fee988843c264c10f90c9a2ede0a0703a2d60bbe10cc3d2fa982a3
pdf-font-stream PDF embedded font (sfnt) at offset 0xDC48 16104 bytes