Malicious PDF — malware analysis report

Static analysis result for SHA-256 aa64b09dec0a9d18…

MALICIOUS

PDF

86.8 KB Created: 2021-06-25 21:26:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: a96e318efc0298d82ce5f4e51ad48e28 SHA-1: ec16dbb0ee6d8e4d2d521fdb17142b9555b36e94 SHA-256: aa64b09dec0a9d188d04c34549d6e05d1a022e4432dac2c829ecbb085e0d330b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF file was flagged by ClamAV and an ML classifier as malicious. It contains numerous embedded URLs that form a link farm, many pointing to compromised CMS upload directories. These links likely serve as lures to phishing sites or malware downloaders, indicating a malicious intent to redirect users to untrusted content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://krisoc.ru/uplcv?utm_term=push+up+exercises+for+chest
    • https://www.alertgy.com/wp-content/plugins/super-forms/uploads/php/files/db8d32d34c0ddfdda5435d308fbcfcaa/ribame.pdf
    • https://retentionstudentexperience.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607de4c5e447f---lesatufumaj.pdf
    • https://noks.cz/wp-content/plugins/formcraft/file-upload/server/content/files/160baccf7cb7ac---9825880176.pdf
    • http://jar-ted.pl/file/21008592561.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160732a4baeabb---kulobejifele.pdf
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/1607efa45cfb4b---kelefodiboxomux.pdf
    • http://www.birapart.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcbd08d662---wajijudem.pdf
    • https://shop-ecobati.com/medias/upload/files/sixonadutijofufok.pdf
    • https://mytutr.com/wp-content/plugins/super-forms/uploads/php/files/2b2f986a42f5655c3f1f973d9848f39b/fotepawozuga.pdf
    • https://aduanaldelvalle.com/userfiles/file/26277234455.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/fb9b739fb3a8145f4e782c029c4872e1/vemuxojagono.pdf
    • https://hacunamatata.ru/wp-content/plugins/super-forms/uploads/php/files/f35ec33cd9642425c934992b7c291190/zugidabokotafamep.pdf
    • http://csc-021.com/userfiles/file/20210617125042_clvlo1.pdf
    • https://mrmusicfoundation.org/wp-content/plugins/super-forms/uploads/php/files/e3js24mcs86bgepm5tldbagbi9/fitafekoziloriporiwi.pdf
    • http://topcudental.com/img/userfiles/files/10773191873.pdf
    • http://dominoliberec.eu/images/file/files/49882308983.pdf
    • http://shmountaineering.co.uk/wp-content/plugins/super-forms/uploads/php/files/eurc0gke65mlhactuts19hrgu6/33806174068.pdf
    • http://www.iycadana.org/wp-content/plugins/super-forms/uploads/php/files/h0fr91gcs659cuvaqr4ec814e1/31308304180.pdf
    • https://cremeconferences.com/wp-content/plugins/super-forms/uploads/php/files/0f37da6ba9789916b6caa5227b5eb44d/rixadipanotegureb.pdf
    • http://bazatalty.pl/wp-content/plugins/super-forms/uploads/php/files/44358b01d87ea1335685689de81e2463/madirul.pdf
    • https://realestateconnect.pro/wp-content/plugins/super-forms/uploads/php/files/gaksrhd38lcf881lhdid810jb1/97634790296.pdf
    • http://metallpress.ru/files/kiguginitajoj.pdf
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/160988534aad9b---gixabi.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_off0000ef64.bin
8e27a802e5deda59620c10f25d2777d893c96e25027299c19ab09c1fc1aad16b
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF64 10468 bytes
font_01_sfnt_off00010763.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10763 16792 bytes
font_02_sfnt_off00011f75.bin
e0de0b0eece35f8fe17abba18cea240198d21402c1788330ca440bc21d7beb53
pdf-font-stream PDF embedded font (sfnt) at offset 0x11F75 17164 bytes