Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5ecc2561f59e2b7…

MALICIOUS

PDF

79.7 KB Created: 2021-09-17 07:47:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-27
MD5: 9d917375b302b2a2f03119481cf4ac63 SHA-1: ae4116892abf60c5e38d6c9cbadd0c19d78f667c SHA-256: c5ecc2561f59e2b70899acea526bbd58388020c975289df549c68a3ac5ebe87a
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains a large number of external links, many of which point to compromised WordPress sites or disposable hosting. The ML classifier strongly indicated maliciousness, and the presence of numerous links suggests an attempt to manipulate search engine results or redirect users to malicious content. No scripts were extracted, and the document body was heavily obfuscated, limiting further analysis of specific user-facing lures.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9978

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=stickman+5+apk PDF link annotation
    • http://audiomaster.se/wp-content/plugins/formcraft/file-upload/server/content/files/1613f1690f1874---pimedexutikevilefosediri.pdfIn PDF document text
    • http://evohome.pl/userfiles/file/josufidut.pdfIn PDF document text
    • https://www.ayersworthglen.com/wp-content/plugins/formcraft/file-upload/server/content/files/16143e1e74ea62---42640651853.pdfIn PDF document text
    • https://seo-methodes.com/userfiles/file/govubuwisowuluba.pdfIn PDF document text
    • http://mercuresamuichaweng.com/admin/file/wafuwav.pdfIn PDF document text
    • http://galettedesrois.eu/userfiles/file/tuzevofevenukun.pdfIn PDF document text
    • https://nhahangbienhaitien.com/uploads/files/87668625502.pdfIn PDF document text
    • http://clingac.es/d/files/55805915469.pdfIn PDF document text
    • https://narellesastro.com/userfiles/files/96961454365.pdfIn PDF document text
    • https://geneolock.com/ckfinder/userfiles/files/lazelevisavepurojerek.pdfIn PDF document text
    • https://www.pferde-fuer-unsere-kinder.de/wp-content/plugins/formcraft/file-upload/server/content/files/1613069f526672---76068290769.pdfIn PDF document text
    • http://sgyscom.com/upload_fck/file/2021-9-11/20210911170147356629.pdfIn PDF document text
    • http://marcelponjee.nl/ponjeefiles/file/dabili.pdfIn PDF document text
    • http://karinameal.ru/imgdish/files/84217205041.pdfIn PDF document text
    • http://originalcheck.it/public/img_admin/file///tobolapakibivoxopalusebot.pdfIn PDF document text
    • http://casaperferiesantamariagoretti.com/writable/public/userfiles/file/72923159559.pdfIn PDF document text
    • http://floral-design-lindgens.de/userfiles/file/77833277897.pdfIn PDF document text
    • https://ercrs.org/wp-content/plugins/super-forms/uploads/php/files/6e7n2bj3nu6948hmkpje9uqn45/7211355833.pdfIn PDF document text
    • http://advairtech.eu/assets/userfiles/file/satoruzosu.pdfIn PDF document text
    • http://pensjonatagat.pl/userfiles/file/sarelul.pdfIn PDF document text
    • http://currycornersugarland.com/admin/images/file/92386663973.pdfIn PDF document text
    • https://www.nobleorthodontic.com/wp-content/plugins/super-forms/uploads/php/files/f31a32662f43f7aa426a024b24707701/jabitirivudipudajokiferam.pdfIn PDF document text
    • http://cluster006.ovh.net/~greeters/namur/ckfinder/userfiles/files/tepuvadenoj.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_off0000cce6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCCE6 20092 bytes
SHA-256: b7dae9fc80e60d70e678e3c1cd976a8ffb2df3d05d41d29e5b37a1b76650a1f6
font_01_sfnt_off0001021b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1021B 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00011a32.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11A32 10272 bytes
SHA-256: 96375e9cc5d7242ca22dbe9d037cfcbc2fd13944b038da494a2285b5760c497f