Malicious PDF — malware analysis report

Static analysis result for SHA-256 a85ae9aacfcbb075…

MALICIOUS

PDF

129.9 KB Created: 2021-06-27 05:37:21 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 4c1dbecd1ed8ac4b1af56cb3b9be3809 SHA-1: 16d8b2859f56afee8369668a4d8d307a3009b2f2 SHA-256: a85ae9aacfcbb075f67807e67ce6dcf854bad825ddc18fa2f12cc7a60961ea30
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs that point to various websites, many of which appear to be compromised WordPress installations. The ML classifier strongly indicated maliciousness, and the heuristic firings suggest this PDF is a link farm designed to redirect users to potentially malicious content. No scripts were extracted, but the sheer volume of suspicious URLs points to a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9950

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://laborke.ru/uplcv?utm_term=extremely+disappointed+crossword+clue
    • https://feriaesotericadeatocha.com/wp-content/plugins/formcraft/file-upload/server/content/files/16082f2968e006---budojujifugeliwapuximume.pdf
    • http://cfh2.com/clients/d/d2/d2a7b52150a7a947468b52e9b7560e3c/File/8332923239.pdf
    • https://www.havanasalsa-dance-tours.com/wp-content/plugins/super-forms/uploads/php/files/9be3941b9b462ee576a0adf63c71baaf/56352170980.pdf
    • http://bahtiyardishekimi.com/fckfiles/file/kanubu.pdf
    • http://alphasigmaoverseas.com/userfiles/file/28404084380.pdf
    • https://www.coconutlodge.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e2b1278499---dofurenaf.pdf
    • https://namratalakhotia.com/userfiles/files/12782275098.pdf
    • http://www.rodnolespropertymanagement.com/siteuploads/editorimg/file/wajuxotasupudo.pdf
    • https://economiadecomunion.net/ckfinder/userfiles/files/tinujilode.pdf
    • http://arci-mp.fr/admin/File/1859691170.pdf
    • http://keacg.com/upload/files/52131444548.pdf
    • http://www.fsnn.se/wp-content/plugins/formcraft/file-upload/server/content/files/1607cae338a97e---jegodunimiwojamup.pdf
    • https://spacio.hk/attachment/file/99302174494.pdf
    • https://fieldofgreen.com/wp-content/plugins/super-forms/uploads/php/files/2ab0ca769b241f856b490c604d846249/53301832873.pdf
    • https://1sis.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ada832b3d26---4512599693.pdf
    • http://www.photobreak.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1607498b120f39---zizineviwojav.pdf
    • http://tropo-design.com/ckfinder/userfiles/files/33258911487.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/160a6625758b9f---wodifa.pdf
    • http://tourister.kr/userfiles/file/vigufasinosagarubep.pdf
    • http://c2mag.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f0207d6672---8349913837.pdf
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/8b333ab2034bdf6821c1b1f03699a266/17717475300.pdf
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/1607aae5773343---mepakikadefopomi.pdf
    • http://cohn-vossen.com/wp-content/plugins/formcraft/file-upload/server/content/files/160713afb1cc5c---57067785842.pdf
    • 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_off00019845.bin
b470bcf01e11e9a4479d07de945ba834def54a449d8d7fa4324d977e390e4fc1
pdf-font-stream PDF embedded font (sfnt) at offset 0x19845 11060 bytes
font_01_sfnt_off0001b215.bin
9fe499e537e41d9ed22f498451ed1c6045174fa55f6a663590ee2c40dad2b14e
pdf-font-stream PDF embedded font (sfnt) at offset 0x1B215 17476 bytes
font_02_sfnt_off0001e019.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1E019 16792 bytes