Malicious PDF — malware analysis report

Static analysis result for SHA-256 21dca02d2805d520…

MALICIOUS

PDF

87.4 KB Created: 2021-09-06 19:47:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-16
MD5: ded298ac566b52d504d76f231467f84b SHA-1: e8c91a4a035a179179fa9e6cde0d7035c057ad66 SHA-256: 21dca02d2805d520dcc83f5375a107d6f1ce68149121e63685406db5a593da40
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload storage, indicating a link farm designed to direct users to potentially malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware distribution. Although no scripts were directly extracted, the PDF structure and URL patterns are indicative of a malicious document, possibly leveraging embedded JavaScript for further actions.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9974

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 http://antik-cafe-bergen.de/wp-content/plugins/formcraft/file-upload/server/content/files/16105cd0ea3de7---60141749213.pdf In PDF document text
    • https://canadianrelocation.net/wp-content/plugins/formcraft/file-upload/server/content/files/160722720a72a0---98875981686.pdfIn PDF document text
    • http://dobraukraina.org/sites/all/sites/dobraukraina.org/files/rigizebunonaxa.pdfIn PDF document text
    • http://www.dnevi-sekretarjev.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606ffa9b62bd6---lonadekemuxevogu.pdfIn PDF document text
    • http://yishiweb.com/upfiles/files/20210801_110504.pdfIn PDF document text
    • https://www.sistemkabin.com/ckfinder/userfiles/files/pibezediriwi.pdfIn PDF document text
    • https://brakos.it/file/7861700622.pdfIn PDF document text
    • https://www.bussmann-tiefbau.de/ckfinder/userfiles/files/miwadejagodupodanug.pdfIn PDF document text
    • https://www.zolmedis.lt/ckfinder/userfiles/files/lavapadap.pdfIn PDF document text
    • http://scissortailfarms.com/wp-content/plugins/formcraft/file-upload/server/content/files/161251397d4aba---dotojutexivinure.pdfIn PDF document text
    • https://diversified-nj.com/wp-content/plugins/super-forms/uploads/php/files/3829cc434242ff5499bcfd68ed099361/50667804551.pdfIn PDF document text
    • http://www.hotel-margherita.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a15bda53e8---68880097267.pdfIn PDF document text
    • https://beachesbrewing.com/wp-content/plugins/super-forms/uploads/php/files/a04adf7b8452ff4df77d6597dff16a69/fulovamimolojivatopak.pdfIn PDF document text
    • https://www.gml.de/wp-content/plugins/formcraft/file-upload/server/content/files/1610835a0834aa---pikuba.pdfIn PDF document text
    • https://www.dartmusicfestival.co.uk/wp-content/plugins/super-forms/uploads/php/files/1fe59c0e8375758e3d2f913795d1493c/51023018046.pdfIn PDF document text
    • https://cffcommunications.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1/1607fabef08815---buzoduduzagawones.pdfIn PDF document text
    • http://anvlaw.com/userfiles/file/lubulisezopalore.pdfIn PDF document text
    • http://simonide.org/userfiles/file/tenepibutim.pdfIn PDF document text
    • https://smartcrm.cloud/upload/files/61379647816.pdfIn PDF document text
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c75421c69f3---kinosaponunizavutef.pdfIn PDF document text
    • http://apvn.info/userfiles/file/pekowexu.pdfIn PDF document text
    • https://portsidestrategies.com/wp-content/plugins/super-forms/uploads/php/files/681bc99327b62da77601e8a3904af01a/87217253385.pdfIn PDF document text
    • https://dsodrecital.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c14b02631dd---9514095582.pdfIn PDF document text
    • https://efsanepin.com/calisma2/files/uploads/viratenukaligutir.pdfIn PDF document text
    • https://roc.mn/uploads/files/zasenimok.pdfIn PDF document text
    • https://feedproxy.google.com/~r/skout/mBVl/~3/Om9ozkHLxGw/uplcv?utm_term=gods+and+goddesses+in+greek+mythology+michelle+houle+pdfPDF 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_off0000ee15.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEE15 18096 bytes
SHA-256: 323351067775d30c1cb9c36a7fa4a095c43c1e091444ade7c217e9ce44198cbf
font_01_sfnt_off00011c7f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11C7F 11412 bytes
SHA-256: 79181aa6a0e30f2e12ac635bc90631cd7c9d77e566af3d535a8bb64f0f673e44
font_02_sfnt_off00013715.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13715 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1