Malicious PDF — malware analysis report

Static analysis result for SHA-256 2ed357c72d3eab0e…

MALICIOUS

PDF

80.1 KB Created: 2021-09-19 04:55:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 3553f065fc47cbbebe3621cf07d61a36 SHA-1: d44498ec5686b3ef9fe7b6ccd49763c794c91df6 SHA-256: 2ed357c72d3eab0e9f2dcb3e7484dcc0e654c5d0c311da77b86e39996658004d
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a high likelihood of malicious intent. Heuristics reveal it functions as a link farm, with several URLs pointing to compromised CMS upload directories. The document body is heavily obfuscated, preventing a clear understanding of its specific lure, but the presence of numerous external links suggests a redirection mechanism to potentially malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://sentralperdana.com/file/jujadoxotabobesogekumaba.pdf
    • http://www.serenissimaservizi.com/files/62274854464.pdf
    • https://giaynangchieucao.com/userfiles/file/dakupolugiwon.pdf
    • http://pelesiuvalymas.lt/i/File/mitafipotinibud.pdf
    • http://covina.crazyrockinsushi.com/uploads/files/64616875212.pdf
    • http://thefutureofgolf.eu/wp-content/plugins/formcraft/file-upload/server/content/files/16137299f84314---rajerutujorajejova.pdf
    • https://lbjgold.in/ckfinder/userfiles/files/86448376303.pdf
    • http://toanlinh.vn/upload/files/towanujokadofibit.pdf
    • http://changrung.com/ckfinder/userfiles/files/rujuxagipopogevudu.pdf
    • https://thefencedocumentary.ca/adminfiles/file/66203270055.pdf
    • https://estudiowebcolombia.com/ckfinder/userfiles/files/35630833851.pdf
    • http://weiddy.com/uploads/files/202109050714298677.pdf
    • http://robbes.nl/media/files/pemin.pdf
    • https://interativacorretora.com/fotosempresa/files/losegebowodevaloxir.pdf
    • https://bistakalikotenetwork.com/userfiles/file/68867935545.pdf
    • https://trinityautorepairs.com/uploads/files/wadokekunowusagubeluxetur.pdf
    • https://www.sabiamente.es/wp-content/plugins/formcraft/file-upload/server/content/files/1612f59f60a9cd---sosajuvixiralaninup.pdf
    • http://exmar.it/foto_fck/file/xisuti.pdf
    • https://martas.vodrsport.cz/uploads/files/63289705795.pdf
    • https://reha.bg/content/upload/file/80654692696.pdf
    • http://tuanayapim.com/rsm/files/veragolazixikarunu.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/16136e56e112d6---43081563161.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/PmAiG5ZyT-k/uplcv?utm_term=uphill+rush+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_off0000d5a7.bin
88d63031537dd2fef206ab0960e994dce5d154235338e2bc623a2f8e94d9e42a
pdf-font-stream PDF embedded font (sfnt) at offset 0xD5A7 18088 bytes
font_01_sfnt_off00010452.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10452 16792 bytes
font_02_sfnt_off00011c69.bin
f16425b3a293566802b4caaa1184d3abca7b29c80f59e47156cfaff11785c1c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C69 10096 bytes