Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa6afab4236687f1…

MALICIOUS

PDF

77.1 KB Created: 2021-09-25 22:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: cebf8fa845eb4b39854b74fe23d9971c SHA-1: 499062d87b4667d38945d537d8a969030e962a0e SHA-256: aa6afab4236687f1ca58390dfdbf41247f7d16db9cdb4415d2b334b9ecad6d62
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file contains numerous embedded URLs, many of which point to compromised or disposable hosting domains, indicating a link farm designed to redirect users. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery through these links. The document body is heavily obfuscated and unreadable, providing no direct content-based clues.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9945

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 http://dkkarsin.pl/img/upload/files/zurexevave.pdf
    • http://streathamtaxi.com/survey/userfiles/files/70019399403.pdf
    • http://xn--brneneskontor-landsforening-b0c.dk/userfiles/file/depuxej.pdf
    • https://ons-station.com/editor_upload/file/mifukokuvidati.pdf
    • https://qualitycountscleaning.com/wp-content/plugins/super-forms/uploads/php/files/c3f8ac2d92eba06b81ee6c572b32050e/xarebozapututujiropegaban.pdf
    • https://semut73.com/contents/files/zokiz.pdf
    • http://sochisushi.nl/survey/userfiles/files/46296439603.pdf
    • http://uteambio.com/upload/files/14466919431.pdf
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/16130c52a41023---76012706932.pdf
    • http://archiw.gbpopatowiec.pl/img/upload/files/dowuvaki.pdf
    • http://expertcomptablecourreges.fr/michel_courreges/userfiles/file/wodedewi.pdf
    • http://xmzhj.com/UserFiles/file/xoligibivilekel.pdf
    • http://giasuminhtam.com/Images_upload/files/25213036969.pdf
    • http://akbmodel.com/wp-content/plugins/formcraft/file-upload/server/content/files/161448e9200878---38791967611.pdf
    • http://ashioke.com/images/library/File/82817128720.pdf
    • http://sys-svinding.dk/userfiles/file/30899288432.pdf
    • http://www.rlktechniek.nl/wp-content/plugins/formcraft/file-upload/server/content/files/16146b9a4d2ea0---41531623243.pdf
    • http://bulmarconsult.com/files/xafilapu.pdf
    • http://gosapahostel.com/userfiles/file/83322971938.pdf
    • http://www.sictombbi.fr/ckfinder/userfiles/files/rajinebidojodizaxovup.pdf
    • https://creativetalentnetwork.com/ckfinder/userfiles/files/tixukodawumuxidixos.pdf
    • https://relaxbotanika.cz/ckfinder/userfiles/files/23361052616.pdf
    • http://tcsklife.com/filespath/files/20210916173529.pdf
    • http://residenzaeden-albisola.com/userfiles/files/90300581579.pdf
    • https://propbrains.com/wp-content/plugins/super-forms/uploads/php/files/b8c3bd04b153648e57f688da2f48dab3/nigupedasigumadogo.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/YTWXjIUwRh0/uplcv?utm_term=periodic+table+pdf+class+10
    • 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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b599.bin
6c67ec6952c88da7e55c73723bf5b44f7a61e57a79ac2c69f7a19a95e3d233f2
pdf-font-stream PDF embedded font (sfnt) at offset 0xB599 16384 bytes
font_01_sfnt_off0000df5e.bin
9b3add2011a99137502593e89ba20e09a8f167030e683d589962374192164127
pdf-font-stream PDF embedded font (sfnt) at offset 0xDF5E 10824 bytes
font_02_sfnt_off0000f841.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF841 16792 bytes
font_03_sfnt_off00011052.bin
01cd0e4798e93fb086042d610f43ddeed7bf091af48aa863f5c4a4f61b651684
pdf-font-stream PDF embedded font (sfnt) at offset 0x11052 16232 bytes