Malicious PDF — malware analysis report

Static analysis result for SHA-256 77862a49289485e1…

MALICIOUS

PDF

87.5 KB Created: 2021-06-27 22:29:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1750517f316305b15e124d9258f879e6 SHA-1: 31053384fc1b35b34b8c72914b7c1492d9440457 SHA-256: 77862a49289485e1d9cfaad81b66aa7d29ed37cb293ab804dc1f14ce9184a024
96 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs pointing to compromised WordPress sites, indicating a link farm designed to redirect users. The ML classifier strongly flagged this PDF as malicious, and the presence of multiple distinct hosts suggests a coordinated effort to distribute malicious links. No scripts were extracted, but the structure and URL patterns are consistent with SEO poisoning or redirector schemes.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://queure.ru/uplcv?utm_term=how+hard+is+it+to+become+a+paleontologist
    • http://www.skupp.pl/wp-content/plugins/formcraft/file-upload/server/content/files/1609faa418e8c9---28097421370.pdf
    • https://westcoastmovers.ca/wp-content/plugins/super-forms/uploads/php/files/74r6dbktbm6j9lfhjm2j7bfetb/jizojelawudep.pdf
    • http://ganan10.co.il/wp-content/plugins/formcraft/file-upload/server/content/files/160a241fc23721---weforagexepuj.pdf
    • https://www.basur-tedavisi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607280419cf3d---lutogazezukakilukak.pdf
    • http://charivne.info/images/file/wugamemorugapu.pdf
    • https://deniz-sogutma.org/img/userfiles/file/vaxobefobogir.pdf
    • http://www.risingstars.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160b87d7de96bf---55658467401.pdf
    • https://skazkavdom.com/wp-content/plugins/super-forms/uploads/php/files/614d87fa0a76e9b1c0365f895943117a/76622518119.pdf
    • http://clinicaveterinariailmarzocco.it/userfiles/files/tegajevunu.pdf
    • http://didocrosby.com/imagenes/file/nuvap.pdf
    • https://bookatowncar.com/userfiles/file/fekog.pdf
    • http://nd-58.ru/wp-content/plugins/super-forms/uploads/php/files/55fe5c06f2fa53d4808f8f2be461cfd6/80397905934.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a0b347287b4---nomujunibuloka.pdf
    • http://universalestetic.com/userfiles/file/mupatifodibotupokatezu.pdf
    • https://sweetestspaparty.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd0f26d53e5---xifuxifunonukok.pdf
    • https://binhvi.com/upload/files/sozugepowusuw.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a136af029e---55416410183.pdf
    • https://adbadog.com/wp-content/plugins/super-forms/uploads/php/files/2c929d43953a37f0d090b877b1fc09d1/juromokajarusevubu.pdf
    • http://www.kissdocs.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160a81c69a0644---84265339325.pdf
    • https://pyhm.ca/wp-content/plugins/super-forms/uploads/php/files/vhoqo7p6jgpbo36cpnebp7eodb/67937520843.pdf
    • http://www.blackhillsdancecentre.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ae7899cfd6b---79854172606.pdf
    • http://www.chinahkcarplate.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a49ed27472f---44987283715.pdf
    • http://nikacarpet.com/My_Project/Hamishe_bahar/ahar_img/files/18008319458.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_off0000f36e.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xF36E 16792 bytes
font_01_sfnt_off00010b80.bin
0af9efdbbf82dd908ae4bafddadf1b9330efabd68fa32a0942ca05874be0f00a
pdf-font-stream PDF embedded font (sfnt) at offset 0x10B80 16692 bytes
font_02_sfnt_off00013704.bin
eebc7db490ceb9b9536d3e5385beae3f118d2f42e32f9dc77532ff586f814d9b
pdf-font-stream PDF embedded font (sfnt) at offset 0x13704 11180 bytes