Malicious PDF — malware analysis report

Static analysis result for SHA-256 dd14b96f7bad97c6…

MALICIOUS

PDF

83.2 KB Created: 2021-09-23 04:37:07 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: b0074c24abb134d6d88fe825f51feab6 SHA-1: 00031a1507f5dca83e53b47358adb58f3fed4006 SHA-256: dd14b96f7bad97c6c6b4ea9223c854ac7195c97c1553dec5da88a2189a013ce2
96 Risk Score

Malware Insights

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

The PDF contains a large number of embedded URLs, many of which point to compromised CMS uploads or disposable hosting. The ML classifier strongly indicated maliciousness. The document body is heavily obfuscated and appears to be generated by wkhtmltopdf, suggesting it's not intended for direct user reading but rather to host links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9925

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://healthlantern.com/ckeditor/ckfinder/userfiles/files/betaxaxafutopit.pdf In PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/57952734236.pdfIn PDF document text
    • https://petala.gr/userfiles/file/wokikuzofodimusebawino.pdfIn PDF document text
    • https://weborder.cloud/userfiles/file///40092884859.pdfIn PDF document text
    • https://www.champagne-cornevin.fr/ckfinder/userfiles/files/negip.pdfIn PDF document text
    • https://mihalex.by/files/files/32850388611.pdfIn PDF document text
    • http://pronobile.com/catalog/file/78855831893.pdfIn PDF document text
    • http://pet.nfe.go.th/m_site/ckfinder/userfiles/files/watowosinagenowigoxi.pdfIn PDF document text
    • https://marcuspietrek.de/MARCUS/files/file/nevugok.pdfIn PDF document text
    • http://thibangoto.com/app/webroot/uploads/files/98666748321.pdfIn PDF document text
    • https://sabresources.com/FCKuploads/file/89595096374.pdfIn PDF document text
    • http://www.alfainstal.pl/wp-content/plugins/formcraft/file-upload/server/content/files/161494e144aa7f---52283940992.pdfIn PDF document text
    • http://www.melodypods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614acaf44e456---1985485372.pdfIn PDF document text
    • https://wcdt.co.th/wp-content/plugins/super-forms/uploads/php/files/vt2bs0cci1i9a5hq0644tvuqbb/duduvubuzivol.pdfIn PDF document text
    • http://bscartridge.com/pic/xopobaninusegopazagukobeg.pdfIn PDF document text
    • http://argra.rs/wp-content/plugins/formcraft/file-upload/server/content/files/16139eb517e5f6---86372291311.pdfIn PDF document text
    • https://jakspravnenapsa.cz/userfiles/file/56196404052.pdfIn PDF document text
    • http://www.hussco-steel.com/husscofiles/files/pewikudaxo.pdfIn PDF document text
    • http://zhfangyuan.com/uploadfiles/files/1055382821.pdfIn PDF document text
    • https://hnhaa.com/userfiles/tnejp/files/85797753740.pdfIn PDF document text
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/metagifogasesidonu.pdfIn PDF document text
    • https://aslimitada.com/userfiles/file/zaribusotuxixarusefefuwa.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/3CAf4wW3hvY/uplcv?utm_term=adobe+lightroom+mod+apk+for+mobilePDF 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 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000b72d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB72D 16060 bytes
SHA-256: 64af0185a2beffa7382febdf957b2ddd2015d3985e5bc97cf8ad64f3c2914973
font_01_sfnt_off0000cc42.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xCC42 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off0000e44f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE44F 1868 bytes
SHA-256: 9d2bb2d94384256bb38bab4c3005c13f44a8b25eb5b232dcefe64ad24aae4b51
font_03_sfnt_off0000ed02.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED02 21660 bytes
SHA-256: c91196acf29a6c05c9e809f244786531e7aa7d3854ca6b6a6111dfa4c625bea0
font_04_sfnt_off00012482.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12482 10888 bytes
SHA-256: a6b5f5320f2965dbef6f8b6eb5f8a2eeaa95da6bb4e3aa1656c3bb8fc41dde3e