Malicious PDF — malware analysis report

Static analysis result for SHA-256 51e32eca75e6c61e…

MALICIOUS

PDF

82.4 KB Created: 2021-09-13 17:43:16 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 1de4da52a13c3bf6acaf8f9157ab1cdf SHA-1: 82c0e068b721a4884896115fe8028fd6a8ad6df1 SHA-256: 51e32eca75e6c61e52d172a555b209dd7d6f46b51d837feedf4734a306c446a5
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to potentially compromised websites or disposable hosting, likely intended to lure users into downloading further malware or submitting sensitive information. The presence of multiple external URIs and link farm heuristics strongly suggests a phishing or scam campaign.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9977

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 https://cructi.ru/uplcv?utm_term=vani+caller+theme+app+download
    • http://iranjobex.com/cache/fck_files/file/xirivalif.pdf
    • https://cherrychile.cl/cherry/uploads/contenido/files/87048428749.pdf
    • https://ms02bet.com/contents/files/ruguw.pdf
    • http://varosom.hu/userfiles/files/xetadigo.pdf
    • https://superpart.com/files/gapofisolabetudelegumosu.pdf
    • https://vicareyou.com/userfiles/file/sikukewokosilud.pdf
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/16132e43ac6c5a---93411201619.pdf
    • https://tradingphrases.net/userfiles/files/76579557185.pdf
    • https://www.hadlowsecurityshutters.com/wp-content/plugins/super-forms/uploads/php/files/292986808cc168cf6c6108b622df3072/sadawet.pdf
    • https://www.officinadelgustoroma.com/wp-content/plugins/super-forms/uploads/php/files/f7e84508014802ab859fc3cae5021a60/45020044788.pdf
    • https://jahanchart.ir/data/files/file/gelitubupokedumovutamigal.pdf
    • https://www.sonorisation-auxerre.fr/ckfinder/userfiles/files/mavopibofomuxinawapekud.pdf
    • https://tradingphrases.net/userfiles/files/58790029214.pdf
    • http://studiogallerani.it/userfiles/files/zidurijenajapafimumuge.pdf
    • https://eslms.com/userfiles/file/dudekad.pdf
    • http://tech-in.info/bramy/userfiles/file/29411484143.pdf
    • https://marblobathware.ph/app/webroot/img/files/kaxeped.pdf
    • http://hb-hospital.com/file_upload/fck_upfile/file/timakumakoremokiris.pdf
    • http://zubrcup.by/files/files/90928867138.pdf
    • https://goez1.com/10005001208290177/ckfinder/userfiles/files/32777928469.pdf
    • http://spzpoz-zdunskawola.pl/upload/file/pumetipafewemaroxiwogev.pdf
    • https://sesconbs.org.br/ckfinder/userfiles/files/37878503905.pdf
    • https://www.budgetskemaet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613ae2dd05e58---pirexurixulosupala.pdf
    • 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_off0000dd99.bin
15a6bce63e40096183dc3f5bb44bb09c32b9e6af1b4e6a953a6fb57a4607399a
pdf-font-stream PDF embedded font (sfnt) at offset 0xDD99 10664 bytes
font_01_sfnt_off0000f5df.bin
491d63dd921cf66d31a860d06f0e301d50771c0a0d3ff47130e0e2c7e813bf9c
pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DF 17688 bytes
font_02_sfnt_off000123de.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x123DE 16792 bytes