Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5565ddeb824ca0b…

MALICIOUS

PDF

79.2 KB Created: 2021-09-15 00:10:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-07
MD5: 68541b280c6a1dcc53876aa32753caf2 SHA-1: 79922bab6d73a39014152a03b0275d090cdf10e3 SHA-256: c5565ddeb824ca0bd509f3b551cdc605ecee906e3236a14230b17c3f6b0b5888
96 Risk Score

Malware Insights

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

The PDF file contains numerous embedded URLs, many of which point to compromised WordPress sites or disposable hosting, indicating a link farm designed to redirect users to malicious content. The ML classifier strongly flagged this PDF as malicious, supporting the assessment that it is used for phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the attack pattern is inferred from the URL structure and heuristic findings.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9981

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://synerhu.ru/uplcv?utm_term=jedi+knight+android PDF link annotation
    • http://annabarons.lv/files/files/21112423405.pdfIn PDF document text
    • http://rafaelstore.ru/upload/files/duguveboxovuruduto.pdfIn PDF document text
    • http://www.ks-klinika.ru/ckfinder/userfiles/files/bexewofutanixitiz.pdfIn PDF document text
    • http://motorlustor.net/userfiles/file/38716153205.pdfIn PDF document text
    • http://abwgulfport.com/uploads/files/mitelaj.pdfIn PDF document text
    • http://nirmalapublicschoolerumely.com/userfiles/file/25674260574.pdfIn PDF document text
    • http://na-bytecek.cz/UserFiles/File/jivawevefobivezotonoz.pdfIn PDF document text
    • http://www.fullmooneye.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613714e2f304d---42810352663.pdfIn PDF document text
    • http://bumsnab.ru/uploads/files/34348007048.pdfIn PDF document text
    • http://reichspfarrer.sk/file/26585640623.pdfIn PDF document text
    • https://amkboiler.com/wp-content/plugins/super-forms/uploads/php/files/e9s31cee9lnfdaiill6ib961qn/dazekujawelapafo.pdfIn PDF document text
    • http://xaydungphongphu.com/uploads/files/24866545098.pdfIn PDF document text
    • https://hightechrustremovers.nl/wp-content/plugins/formcraft/file-upload/server/content/files/161395cc47616a---25051286403.pdfIn PDF document text
    • https://adiwirawanbali.com/wp-content/plugins/super-forms/uploads/php/files/87fc98492765659a8667a3f4f39a1487/darezomunabudipo.pdfIn PDF document text
    • http://fairway.cc/images/blog/file/xudakaze.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/161401aade370b---92813468307.pdfIn PDF document text
    • https://totalyoumovement.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613d455fd3d1c---jukolabibatan.pdfIn PDF document text
    • http://cnex.cc/images/blog/file/mevalopotetikik.pdfIn PDF document text
    • http://greensquares.in/userfiles/file///nawurepekifijux.pdfIn PDF document text
    • https://ncfouting.com/wp-content/plugins/formcraft/file-upload/server/content/files/16130dce395472---44534252618.pdfIn PDF document text
    • http://benetworkingpro.com/ckfinder/userfiles/files/37691222493.pdfIn PDF document text
    • https://bxthirteen.wpengine.com/wp-content/plugins/super-forms/uploads/php/files/fa9dcd55cb7cf0799de60fb61f830e07/50227683647.pdfIn PDF document text
    • 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_off0000d1ae.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD1AE 10396 bytes
SHA-256: f26793ae177f545341c051eb3f7f291d8710e9dbef8c8be5c02a87f1bb790be4
font_01_sfnt_off0000e8ef.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8EF 17748 bytes
SHA-256: cbc5fa0165bbd0123e67bb5575ac138800ab092cf3cf47dedeaca3341bde339a
font_02_sfnt_off00011752.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11752 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1