Malicious PDF — malware analysis report

Static analysis result for SHA-256 a9f3dcca63d34dc5…

MALICIOUS

PDF

86.4 KB Created: 2021-07-06 15:19:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f23ea6312f8b821967c3676507d7db04 SHA-1: c18bf563f65509215b98cd042453ea64478773fb SHA-256: a9f3dcca63d34dc5e5a6b2501d3ecae6a48940c3ffbc33a808fe36214fdff51a
156 Risk Score

Malware Insights

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

The file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. It functions as a link farm, with numerous URLs pointing to compromised or disposable hosting, suggesting it's used for phishing or distributing further malware. The PDF structure and link farm characteristics are consistent with common techniques for luring users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

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://sosnovgeo.ru/userfiles/file/sinegaviwirimokuluni.pdf
    • https://relleno-acidohialuronico.com/wp-content/plugins/super-forms/uploads/php/files/fa9165ae9383f8e6d17e00f5cebd7a9c/40879566334.pdf
    • http://batterseataxi.com/survey/userfiles/files/5918422157.pdf
    • http://uat.ideadunes.com/projects/ideadunes-portfolio-site/wp-content/plugins/formcraft/file-upload/server/content/files/160bfa759bee98---28812460920.pdf
    • https://brusroom.com/wp-content/plugins/super-forms/uploads/php/files/ab1647586ece62c54c78c4a066971bdb/kerofiwaxujuf.pdf
    • https://sabunwangi.com/contents//files/zibudotowinufarinebowufe.pdf
    • https://cncostruzioni.com/userfiles/file/1356257609.pdf
    • https://www.apartamentselsllacs.com/wp-content/plugins/super-forms/uploads/php/files/inn0q5sfqdofblgq98qm63vf3f/76596392089.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/5qgn3ctjn8oikc097vvfenlcs2/lusudomiwisemejirisufe.pdf
    • http://musiclivemarsala.com/userfiles/files/48344754888.pdf
    • http://www.minaakshimajumdar.com/fckimages/file/xenokomufo.pdf
    • http://bsbcarpet.com/userfiles/file/1063232655.pdf
    • http://trackeg.com/en/wp-content/plugins/formcraft/file-upload/server/content/files/160965559c6915---83906635553.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/61887e91e58a3023096ac3ad74deb08a/56452161039.pdf
    • https://www.citysecurity.org.uk/wp-content/plugins/super-forms/uploads/php/files/kcdm655nqs00ujiv7epldks2i9/74744463840.pdf
    • https://www.teppiche-waschen-hamburg.de/wp-content/plugins/formcraft/file-upload/server/content/files/16084de7cf2bb6---80084277392.pdf
    • http://exmar.it/foto_fck/file/wiketagasagapufomurajizo.pdf
    • https://tcufroghouses.com/wp-content/plugins/formcraft/file-upload/server/content/files/160822f290a264---3537240109.pdf
    • https://fiambreszav.com/wp-content/plugins/super-forms/uploads/php/files/de67487287e0a73490e6a0b70ccb6490/58375419885.pdf
    • https://hartwellcook.com/wp-content/plugins/super-forms/uploads/php/files/20dd8c651481bfb61e979b4913120768/vijiviwakapubakifel.pdf
    • http://kaufdeinauto.de/wp-content/plugins/formcraft/file-upload/server/content/files/160c2100861ccf---pumekejorojezobowul.pdf
    • http://zadonskiy.ru/wp-content/plugins/formcraft/file-upload/server/content/files/1608826c282fc8---68380598672.pdf
    • http://parkwestresidences.com/wp-content/plugins/formcraft/file-upload/server/content/files/16091c5756a62a---dotorojetozan.pdf
    • https://avis-medical.ma/wp-content/plugins/super-forms/uploads/php/files/f9fdfb49cd93b2571fc6655d2b242554/xubinolulutezanagebal.pdf
    • https://prsnashville.com/wp-content/plugins/super-forms/uploads/php/files/e31948e02b21ab98ee7a9b5f6037fc65/lijakoxejetexawug.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/BvfzZFkJO3s/uplcv?utm_term=royden+4th+edition+solutions
    • 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_off0000eeac.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEEAC 16792 bytes
font_01_sfnt_off000106be.bin
a8fe9baf819cf5ef9027e0eaeb42bad47f028864eb681071d764f059d4e812a1
pdf-font-stream PDF embedded font (sfnt) at offset 0x106BE 17448 bytes
font_02_sfnt_off0001349d.bin
69e7f0e136d765ce687ab7a606b7b2fd91b89726fc8c6b2c4dc4790b59b53c56
pdf-font-stream PDF embedded font (sfnt) at offset 0x1349D 10420 bytes