Malicious PDF — malware analysis report

Static analysis result for SHA-256 d71a49aceb49bedc…

MALICIOUS

PDF

84.8 KB Created: 2021-07-20 20:42:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-13
MD5: 725d0ba26400cefca7ae257c83325942 SHA-1: 2c4e376690f8b207da680c6a432bcf96a7adf301 SHA-256: d71a49aceb49bedc4747230db7c749c475c43e36d14ee622c554aacb42471ecd
156 Risk Score

Malware Insights

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

The PDF contains numerous embedded URLs, many of which point to compromised WordPress sites and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely to redirect users to phishing or malware distribution sites. The file's structure and URL patterns are consistent with SEO poisoning or link farm techniques used to lure unsuspecting users.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

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://kisikana.hr/userfiles/file/83210886895.pdf In PDF document text
    • http://www.mustwalge.ee/data/content/files/61703346020.pdfIn PDF document text
    • http://www.dj-csnl.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160a5dd27eb40f---vewulovexawomawolete.pdfIn PDF document text
    • https://medosojewellery.com/userfiles/files/71841783092.pdfIn PDF document text
    • http://fixafilm.se/userfiles/file/34505685327.pdfIn PDF document text
    • http://bukhatirhomes.com/userfiles/file/94956627342.pdfIn PDF document text
    • http://dezmaster.com/userfiles/file/9059235015.pdfIn PDF document text
    • http://www.ibadirect.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609f9199db945---bapof.pdfIn PDF document text
    • http://thanhtindesign.vn/uploads/image/files/79172366019.pdfIn PDF document text
    • http://topopentertainment.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bdfc76c4c16---22141195053.pdfIn PDF document text
    • http://anm-av.de/uploads/files/musaxisunosemekaverakuxot.pdfIn PDF document text
    • https://yepsell.com/userfiles/files/7897878929.pdfIn PDF document text
    • https://riverasphotovideo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c57654e2763---32934382698.pdfIn PDF document text
    • http://nail-free.com/ckfinder/userfiles/files/xuradegodojekawid.pdfIn PDF document text
    • http://panhongbo.com/ckfinder/userfiles/site_eachfun_com/files/dexeguvunivokidafivize.pdfIn PDF document text
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/dc40ae8d1e49b5ca68887a135af138ea/87871589374.pdfIn PDF document text
    • https://regalcabs.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/1607bb957acca4---35648176312.pdfIn PDF document text
    • https://sportsslife.net/upload/ckfinder/files/62833815319.pdfIn PDF document text
    • http://prestopc.it/upload/file/sikedexabarozu.pdfIn PDF document text
    • http://discoveryenglish.org/wp-content/plugins/formcraft/file-upload/server/content/files/1608356ea3a14a---1494990023.pdfIn PDF document text
    • http://chi-kara.net/userfiles/file/pijojusugukanonojo.pdfIn PDF document text
    • http://rydelko.pl/userfiles/file/vinate.pdfIn PDF document text
    • https://cashofferoregon.com/wp-content/plugins/formcraft/file-upload/server/content/files/160f3ec508686e---76638157728.pdfIn PDF document text
    • https://asiastudy.in/ckfinder/userfiles/files/gokub.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1KS0DP0cxss/uplcv?utm_term=1+cup+butter+in+tablespoonsPDF link annotation
    • 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_off0000e8fa.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE8FA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off00010111.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10111 10564 bytes
SHA-256: 6965d9ff4e47259eac207253eb317ad34910362e32d72d696af4b69f17928e77
font_02_sfnt_off00011910.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11910 17200 bytes
SHA-256: 9de97fc83e5a5ede3ef2a657411c6dd74717013cba7e61a5558a0491012eb510