Malicious PDF — malware analysis report

Static analysis result for SHA-256 8b839dfc58550b96…

MALICIOUS

PDF

86.8 KB Created: 2021-07-15 21:15:26 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 240284c653deaea1731a19410ba6be13 SHA-1: 3c5d33f64ef7470f1183eb96b075ba685249a143 SHA-256: 8b839dfc58550b96bfe9fce39584ef60fc294ac6e4999100fefcfb8f5b2b0586
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This 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 URLs pointing to compromised CMS upload directories, likely intended to lure users to malicious sites. The document body was unreadable, but the heuristic firings strongly suggest a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

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://metroguards.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/1607f8e34196d5---dirogexifunatowefomum.pdf
    • http://koszyczarek.pl/userfiles/file/43671399756.pdf
    • https://glosunspa.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072197b94ef7---nufodukixoxovajijo.pdf
    • http://brodart01.com/wp-content/plugins/super-forms/uploads/php/files/6s948320oab2h5p0vgbh33pusa/jafukizav.pdf
    • http://jtour.vn/userfiles/file/88206653556.pdf
    • http://pansophers.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609632ce70e59---16836638042.pdf
    • https://utilitydiscount.com/wp-content/plugins/formcraft/file-upload/server/content/files/160781eed362c2---dakitomaligego.pdf
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210605_678A0E61A29C7809.pdf
    • https://www.webhisto.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/160a5de39b7a46---pisudixi.pdf
    • http://bamt.be/wp-content/plugins/formcraft/file-upload/server/content/files/160984488d97c1---jepibikopinu.pdf
    • http://zulassungsservice4you.de/bilder/file/posugeruzuxawupi.pdf
    • http://asesorialuishervas.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a962d8f419d---29532416731.pdf
    • https://szalkasszorutacskok.hu/app/webroot/files/content/files/gaxodebavakanapanetatisov.pdf
    • http://kasargod.net/uploads/file/xupituzewutowefezeliwum.pdf
    • https://www.aceitedeoliva.com/wp-content/plugins/super-forms/uploads/php/files/6ca73f42d4afcf1aabc72af6d937c598/xuvojamagutaworubiwuxi.pdf
    • https://certifiedmoversinc.com/wp-content/plugins/super-forms/uploads/php/files/f127491895d111d7badafe5d70d48510/kimurefavubika.pdf
    • http://associacaoguainumbi.org.br/wp/wp-content/plugins/formcraft/file-upload/server/content/files/160833d6d87c29---midufar.pdf
    • https://hsegroup.ru/wp-content/plugins/super-forms/uploads/php/files/cquc7evvnaot186ef0j6sas271/43849388795.pdf
    • http://nemdanangpho.com/uploads/2021-05-28/images/files/munumiputiwodosiropejud.pdf
    • https://www.heainc.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608074c5ac1b4---17834960488.pdf
    • https://www.kiteschule-eckernfoerde.de/wp-content/plugins/formcraft/file-upload/server/content/files/1606fcc47e9014---tuwolefimebu.pdf
    • https://manenshop.com/upload/files/2927712155.pdf
    • http://www.tenniscanberra.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/160806e3ad54ef---37158065623.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/1xuhb7AK25c/uplcv?utm_term=types+of+deontological+ethics
    • 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_off0000f1ad.bin
73f18b17adee40f319e9dbfaa65ab718e437e51d19bc8d5d4ad6b94508fe05f4
pdf-font-stream PDF embedded font (sfnt) at offset 0xF1AD 10876 bytes
font_01_sfnt_off00010a96.bin
461dbf22cb3623be4e3a9795d5cfaf7bc89ef83bcf0746f6e10255fede0204ac
pdf-font-stream PDF embedded font (sfnt) at offset 0x10A96 16576 bytes
font_02_sfnt_off000135a8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x135A8 16792 bytes