Malicious PDF — malware analysis report

Static analysis result for SHA-256 843880d0b4e12e30…

MALICIOUS

PDF

81.9 KB Created: 2021-09-16 03:38:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9bfa155c84176cdf8e27a2d334796793 SHA-1: fe05f3d6b4e9668fb7dd21c01f0c5c3b264496dd SHA-256: 843880d0b4e12e30da3077ec486085a2dd8a584b313c9ced85e643d2ea75df59
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The file was identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it functions as a link farm. The embedded URLs, such as 'https://queure.ru/uplcv?utm_term=cyberpunk+2077+game+apk', suggest a lure to potentially malicious content. The PDF structure and numerous external links point towards a phishing or malware distribution attempt, likely delivered as a spearphishing attachment.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9955

Heuristics 6

  • 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.
  • 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://queure.ru/uplcv?utm_term=cyberpunk+2077+game+apk
    • https://cicimanis.com/contents/files/rosugunisijezoxalepubube.pdf
    • https://homeuu.biz/upload/ckeditor/pages/files/ruvexu.pdf
    • https://m-isc.com/userfiles/file/23362850715.pdf
    • http://rebornfair.com/FileData/ckfinder/files/20210913_58089CB97939EBFA.pdf
    • https://paymentor.nl/uploads/file/jikufe.pdf
    • http://secureyun.cn/uploadfile/file///2021091606283027.pdf
    • https://www.pactforfamilies.org/ckfinder/userfiles/files/gitokuduburonimezevirera.pdf
    • http://naplesredeals.com/userfiles/files/70603584368.pdf
    • https://radekslodkiewicz.pl/files/file/wokezakuwesagul.pdf
    • http://abwcrainhwy.com/uploads/files/95557729029.pdf
    • https://vntdc.com/upload/fck/file/5065726462.pdf
    • http://steclotildehorton.ca/wp-content/plugins/formcraft/file-upload/server/content/files/1613b4cf29b49a---wapepugepiga.pdf
    • http://www.hcibatiment.fr/wp-content/plugins/formcraft/file-upload/server/content/files/161358990ed480---96806204170.pdf
    • http://mycoapaisyl.com/webimages/files/maxefugabedivagebok.pdf
    • https://ultralloy.net/upload/files/74221767684.pdf
    • https://alkhairi.co.uk/wp-content/plugins/super-forms/uploads/php/files/0282f83951ebee90b7ad138c5ba3309c/tewakewogogepotopap.pdf
    • https://kisikana.hr/UserFiles/files/34969610187.pdf
    • http://aci-immobilier-douai.fr/userfiles/files/6505212117.pdf
    • https://lescourailleurs.com/upload/editor/file/walewimaxafinabapubiseb.pdf
    • http://www.physedu.in/newsite/userfiles/files/34407164421.pdf
    • http://facyt.com.ar/ckfinder/userfiles/files/55270472846.pdf
    • http://www.goataxiservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613890ba2c56e---30451903618.pdf
    • http://abwclayton.com/uploads/files/gikubosomomawuxunob.pdf
    • http://tao-oita.com/admin/upload_filesfile/45455402472.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_off0000d9cc.bin
dea9c7a9277000f6acfeb93c21d38c646dfe002738e5f1e25e0e4afb833833e0
pdf-font-stream PDF embedded font (sfnt) at offset 0xD9CC 18308 bytes
font_01_sfnt_off0001095a.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1095A 16792 bytes
font_02_sfnt_off00012171.bin
54ac5b6686489489b2de1b278d1f64c583df5ea615ce2d266fb4cdfd8c89f287
pdf-font-stream PDF embedded font (sfnt) at offset 0x12171 10840 bytes