Malicious PDF — malware analysis report

Static analysis result for SHA-256 842506da707b6c25…

MALICIOUS

PDF

83.0 KB Created: 2021-09-19 04:54:52 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: d7bb6c73e03154cdc1ee50b659c3782a SHA-1: 60c6a9ec7fd3e6c9b3bf481ee4c27e22d0b72323 SHA-256: 842506da707b6c253a9563aac8e352181fe6bb4e7ae341b82dde70fe1d69a471
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains multiple heuristic firings indicating it is a malicious link farm designed to redirect users to other malicious PDFs. The ML classifier and ClamAV detection strongly suggest malicious intent. The embedded URLs likely serve as a mechanism to download and execute a second-stage payload, although no specific script was extracted to confirm this.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9985

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 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.
  • 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://wxbeimei.cn/upload/ckimg/files/202109031230596171.pdf
    • https://dazzlin.co.uk/wp-content/plugins/super-forms/uploads/php/files/8ddc93f57ddf1dc182c9292b1aa14142/60809960788.pdf
    • http://xinghui.co/upload/ckimg/files/202109162220444457.pdf
    • http://elektro-galerie-hamburg.de/userfiles/file/94981320907.pdf
    • http://studioriboldi.eu/userfiles/files/61243265089.pdf
    • http://cavusofis.com/images_upload/files/wubemafabowazikezodol.pdf
    • http://www.magicapro.it/wp-content/plugins/formcraft/file-upload/server/content/files/161343bae17bdc---perorawalapegamazelujut.pdf
    • http://ufcnagykanizsa.hu/userfiles/file/27110948554.pdf
    • http://gemaeldeundobjekte.de/uploads/files/zusomurode.pdf
    • http://cherryontop.pl/upload/fotki/file/65571339750.pdf
    • http://studiomedicoveterinariobellucci.eu/userfiles/files/31126109718.pdf
    • http://pilot-market.ru/new/files/file/lunifewe.pdf
    • https://secolink.sk/userfiles/file/karevasavumelepezowotij.pdf
    • http://sintniklaas.kinderopvangpimpeloentje.be/ckfinder/userfiles/files/57519798601.pdf
    • http://bpabv.nl/uploadfiles/file/redenikulodixipos.pdf
    • http://tencanpowder.com/d/files/mojodevejawatunigexonuf.pdf
    • http://alda.pl/ckfinder/userfiles/files/xaporivelukabewo.pdf
    • https://abzesolar.com/uploads/files/pudaloxusizoji.pdf
    • http://yidaig.com/uploadfile/file/20210902231813.pdf
    • http://sdds.be/userfiles/file/90223062873.pdf
    • https://travellifeafrica.com/ci/userfiles/files/4438515382.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=ad+free+mod+apk
    • 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_off0000e1ef.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1		 pdf-font-stream PDF embedded font (sfnt) at offset 0xE1EF 16792 bytes
font_01_sfnt_off0000fa01.bin
32c54943d5e9f2d451054add133f4589b7d143654116892eb0802db0c38d73d2		 pdf-font-stream PDF embedded font (sfnt) at offset 0xFA01 17648 bytes
font_02_sfnt_off000127b3.bin
2b0c8508ed8df08c3466a62563839257394c9f7c523a2c8e82360f102d226a6b		 pdf-font-stream PDF embedded font (sfnt) at offset 0x127B3 10224 bytes

Open this report in the interactive analyzer, or submit your own file for analysis.