Malicious PDF — malware analysis report

Static analysis result for SHA-256 abbec80ba8e8f22d…

MALICIOUS

PDF

70.7 KB Created: 2021-10-03 09:34:09 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-31
MD5: fc279831349216b65dab74bf8b73c817 SHA-1: 0a859ba81381d9baac3db2f6d95fe43558f4411c SHA-256: abbec80ba8e8f22d1ed7a9839cc537d062e142d9017d83f7b154a74cac0a074d
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to domains identified as link farms or hosted on compromised CMS upload storage. The ML classifier strongly indicated maliciousness, and the structure suggests an attempt to lure users to external, potentially malicious, content. The primary function appears to be redirecting users through a network of disposable or compromised domains.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9893

Heuristics 5

  • 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://comtraining.cl/userfiles/files/67779347670.pdf In PDF document text
    • http://jyy.jp/ckfinder/userfiles/files/20210922_163752.pdfIn PDF document text
    • http://hotstamping.pl/files/file/15548311507.pdfIn PDF document text
    • https://equalland.com/uploads/File/42950899261.pdfIn PDF document text
    • https://aldea.work/wp-content/plugins/super-forms/uploads/php/files/b0e14f2fb56ff12571083a1803e3539a/12181334715.pdfIn PDF document text
    • https://brs.jo/userfiles/files/xazaruje.pdfIn PDF document text
    • https://dazhonghua1688.com/ckfinder/userfiles/files/30490890973.pdfIn PDF document text
    • https://un7un9b3rl1pa7-99.com/contents/files/tudelajamosiwavi.pdfIn PDF document text
    • http://citysoupsbellevue.com/uploads/files/61498959586.pdfIn PDF document text
    • http://icsbc.ru/fuploader/file/91560195069.pdfIn PDF document text
    • https://goodluckfishing.com/ckfinder/userfiles/files/vukivu.pdfIn PDF document text
    • https://dienmayngalinh.com/img/files/depukitibevavuxovutonija.pdfIn PDF document text
    • https://sketchup360.vn/wp-content/plugins/super-forms/uploads/php/files/nj9fnfvaevtdf1p7hosleh2c6f/jelujubububasomegu.pdfIn PDF document text
    • http://www.mmd.ntou.edu.tw/ckfinder/userfiles/files/41549751185.pdfIn PDF document text
    • https://www.pharmawell.eu/ckfinder/userfiles/files/jalividobukekifiv.pdfIn PDF document text
    • http://diamant-x.sk/UserFiles/file/tojazakozojibenulibebu.pdfIn PDF document text
    • http://richardchong.com/userfiles/files/55910840961.pdfIn PDF document text
    • http://www.rpv-drachten.nl/files/file/kowezusejivada.pdfIn PDF document text
    • https://iphastkala.com/userfiles/file/36656992053.pdfIn PDF document text
    • http://ansing.nl/userfiles/file/69060935487.pdfIn PDF document text
    • http://k12kos.com/ckfinder/userfiles/files/10336420500.pdfIn PDF document text
    • http://vigova.vn/Images_upload/files/99349477722.pdfIn PDF document text
    • http://lyzjkgm.com/d/files/xubajemero.pdfIn PDF document text
    • http://castel.lu/userfiles/files/33661631962.pdfIn PDF document text
    • https://hmv.ir/wp-content/plugins/formcraft/file-upload/server/content/files/161431e03857c4---tidojefibaxubebipuxifu.pdfIn PDF document text
    • http://www.derbysignandgraphics.com/uploads/file/surefogufimamuru.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/PmAiG5ZyT-k/uplcv?utm_term=my+mother+your+mother+poemPDF link annotation
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b24a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB24A 17184 bytes
SHA-256: 563eee040fb9a5d10cc78261838a698a15211bd263de682cf3e563b43fdc8842
font_01_sfnt_off0000de48.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDE48 10152 bytes
SHA-256: 97984fea785cce7dac3ae72c89f08dffeace54bda61dd5cb3ee22f3ef095ebda
font_02_sfnt_off0000f503.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF503 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1