Malicious PDF — malware analysis report

Static analysis result for SHA-256 ef897e31bd7459f6…

MALICIOUS

PDF

109.2 KB Created: 2021-06-29 02:05:40 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: e6334229c02ab63c91e8d361d2710cd2 SHA-1: aa90b674bc92936d8d149a5ee1dfb06de9e0eec8 SHA-256: ef897e31bd7459f6b9b48b79671e5ceec707f3711ef526f441bbc4345773944a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of embedded links, many of which point to compromised WordPress sites. The heuristic 'PDF_SEO_DISPOSABLE_LINK_FARM' indicates this is likely a link farm designed for SEO manipulation or to distribute further malicious content. No scripts were extracted, and the document body was unreadable, but the link structure strongly suggests a malicious intent to redirect users to potentially harmful websites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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://www.kunapak.com/wp-content/plugins/super-forms/uploads/php/files/3eegav9ovrjsrvoddmgtmok9ua/14609270563.pdf
    • http://www.platformliften.info/wp-content/plugins/formcraft/file-upload/server/content/files/160700ec2aafd3---luboluwitekilo.pdf
    • https://www.adler-leitishofen.de/wp-content/plugins/formcraft/file-upload/server/content/files/1608655f31077e---xalisubukemin.pdf
    • https://www.escon.it/wp-content/plugins/super-forms/uploads/php/files/2afff9cbf538d90d3e0c2253edf3a14c/44892899209.pdf
    • https://weeb.nu/userfiles/file/85984918354.pdf
    • https://www.auditek.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607b6d7c8c0da---89778254594.pdf
    • http://vasilii-orlov.fun/wp-content/plugins/super-forms/uploads/php/files/53e8bd275b0a403de19701a6a4be0960/wirudanatuverirezixumubeb.pdf
    • https://www.mercedesbenzofaustinservice.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d28e52fb54---zedonasaverenomofa.pdf
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/hs61nemaqkklrjfanhq9t8ljk9/39736460357.pdf
    • http://globalquestconsulting.com/userfiles/files/fegimenajerovut.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/1606f8ea18ea17---dulowatobosagisip.pdf
    • http://extracam.es/app/webroot/arxius/file/4583493618.pdf
    • http://kennyre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b568a5cdaad---13909225745.pdf
    • http://asu.com.vn/wp-content/plugins/super-forms/uploads/php/files/etnvfak0vkokfdeg0arbf239ab/78010603350.pdf
    • http://bjhtdszdh.com/v15/Upload/file/20216202229375290.pdf
    • http://www.iso-clean.fr/wp-content/plugins/formcraft/file-upload/server/content/files/16086825d81a9d---xuzijutumodizokajo.pdf
    • https://photographerin.agency/wp-content/plugins/super-forms/uploads/php/files/jb726pte3fdo9fa6p7lkba7nq4/73591896037.pdf
    • https://cambodiaangkorhomestay.com/userfiles/file/libeziwa.pdf
    • https://www.projectorrentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607d5f8578607---63177928249.pdf
    • http://jump360.co/upload/files/20210625124444.pdf
    • https://primeodontorj.com/wp-content/plugins/super-forms/uploads/php/files/8f9086a51be009f84b45c2b79e7d830e/veselunipuzuvusosizosob.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/3vuEKuznOb8/uplcv?utm_term=do+you+need+to+wear+a+helmet+when+riding+a+bike
    • 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_off0001476a.bin
d701ab795dd4c5c3c4a2ff6d77fbcc48f1887a96bad23ff4d327b71312ddd2a4
pdf-font-stream PDF embedded font (sfnt) at offset 0x1476A 11060 bytes
font_01_sfnt_off000160cd.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x160CD 16792 bytes
font_02_sfnt_off000178df.bin
a4ab9f0fe62092639dd71730571ceb32b0cf068d0caff08cfb866e45203690d3
pdf-font-stream PDF embedded font (sfnt) at offset 0x178DF 17760 bytes