Malicious PDF — malware analysis report

Static analysis result for SHA-256 894b6f240cc4cf66…

MALICIOUS

PDF

67.0 KB Created: 2021-09-06 22:28:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 823a30d9d7002a2a1f6dabd3d530735f SHA-1: c5d801f94be9453b4aa481a00fe96e8dc30cf417 SHA-256: 894b6f240cc4cf6602d40737b96dd67409b090667ab2d51e952ca0f50d2a3cf3
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF is identified as malicious by ClamAV and ML classifiers, exhibiting characteristics of a phishing lure. The heuristic PDF_IMAGE_LURE indicates it's an image-based document designed to trick users into clicking an embedded URI. Multiple heuristics point to link farms on compromised CMS uploads and disposable hosting, suggesting the PDF serves as a redirector to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9997

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 66 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://xn--80aaa1anac6cg.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/9b34aa453275ec8f0347bdf8aa8bbb05/16514138044.pdf
    • https://www.fmworks.com.tr/wp-content/plugins/super-forms/uploads/php/files/csef3khtuvegamfvl383k8djjq/bijisewopitifenujefakim.pdf
    • http://whs1963.com/clients/7/75/758a827d59fb1c2827eec60421ffdc22/File/93173564229.pdf
    • http://netdepphunu.vn/images/userfiles/file/568984063.pdf
    • https://fmpride.com/wp-content/plugins/super-forms/uploads/php/files/6117d252584c69f3a3d26340760cd42a/lakosogedekamazij.pdf
    • https://lesura.net/userfiles/file/48767241080.pdf
    • https://syteq-pro.com/userfiles/file/77768604819.pdf
    • http://dogalakustik.com/depo/sayfaresim/file/34831675960.pdf
    • http://proxima-design.cz/files/file/talejixonag.pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/1607c414a6dd48---jixepejufipuvoz.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16118dffac43ae---51720026028.pdf
    • http://cga82.com/admin/File/bawuzadotapen.pdf
    • http://xn--spreewaldpension-lbben-9lc.de/meineBilderAlbertGrundschule/file/38715297220.pdf
    • http://nbkhjc.com/uploads/202108/file/210811124744639515b5p76yxgrb4g.pdf
    • http://visualpaint.com/wp-content/plugins/formcraft/file-upload/server/content/files/16077d45762881---lexejov.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/S30rS-6n6vg/uplcv?utm_term=higher+order+derivatives+product+rule+quotient+rule+worksheet
    • 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_off0000a9ee.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xA9EE 16792 bytes
font_01_sfnt_off0000c200.bin
c2929a18555eb0c0893a76bcae85cce70464723a3e873513f88f8f3561baa0a7
pdf-font-stream PDF embedded font (sfnt) at offset 0xC200 13884 bytes
font_02_sfnt_off0000e43d.bin
03da53206ac334897ad37323ef019e1c3bed1b03f906105f83a25c5757a37f7e
pdf-font-stream PDF embedded font (sfnt) at offset 0xE43D 11276 bytes