Malicious PDF — malware analysis report

Static analysis result for SHA-256 b28ca3dae2b6ae58…

MALICIOUS

PDF

78.8 KB Created: 2021-06-26 22:42:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 374a31beecda428b5afc2eae9956e655 SHA-1: c6adbcc624637d07a5c9c971775f4332bf74780c SHA-256: b28ca3dae2b6ae582b8c5d5b6f43e058433e1cb470f33aa4d4494052201ed065
156 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with multiple heuristics indicating it is a link farm hosted on compromised CMS uploads. The embedded URLs point to various domains, many of which are associated with compromised WordPress sites, suggesting a phishing or malware distribution scheme. No scripts were extracted, but the structure and URL patterns are indicative of a malicious PDF.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9949

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://antwerp-rentals.com/wp-content/plugins/formcraft/file-upload/server/content/files/16078f253795ab---77892955097.pdf
    • http://stepasidemedical.com/images/uploads/file/14761216424.pdf
    • http://flightshop.jp/images/blog//file/1069014323.pdf
    • http://elonsummerstorage.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c9305bef36e---nopibuberexowaro.pdf
    • http://snookerfootball.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609d6f5c25171---zitotemodinusot.pdf
    • http://xn--o39a91gvwm83kbsn.com/FileData/ckfinder/files/20210617_3FFCE15E184C3582.pdf
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160bd8523e66e1---1545516068.pdf
    • https://www.reliancecareuk.com/wp-content/plugins/super-forms/uploads/php/files/3cf952f4da5ab66401effaf3fffed5e1/61372214582.pdf
    • https://archltginc.com/wp-content/plugins/super-forms/uploads/php/files/c59f3278db3b691c0f73eaafd82c6b84/bavolobipup.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/cg3hllvteiiptdqdmcur0h4q59/dugur.pdf
    • https://avenirpourtous.fr/wp-content/plugins/formcraft/file-upload/server/content/files/1607a978e4aadc---70408021961.pdf
    • https://www.infratechgroep.nl/wp-content/plugins/super-forms/uploads/php/files/e4ac8c85db2308e7f9fb584ef5596804/koxarigawilu.pdf
    • http://studiotecnicoforace.eu/userfiles/files/76386035884.pdf
    • https://www.ideaklinikizmir.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607332f39a6ea---povawozilir.pdf
    • https://www.idromeccanicasrl.com/idromeccanicasrl.com/wp-content/plugins/super-forms/uploads/php/files/5d0806ca4bd87722ae56af8539c16b2b/14447164440.pdf
    • https://www.hintonassociates.com/wp-content/plugins/super-forms/uploads/php/files/eb4e189572e38ef3afa30731917f8e71/noberimezifesa.pdf
    • http://www.julitolaschools.com/wp-content/plugins/formcraft/file-upload/server/content/files/16070a5baf373d---62712069952.pdf
    • https://gift-edu.ru/wp-content/plugins/super-forms/uploads/php/files/a18585f901b6bdcf5f4938858c940d88/79201660110.pdf
    • http://www.tif.cn/wp-content/plugins/super-forms/uploads/php/files/fadtq3i702jhkn8pu15ksi2ern/61130122634.pdf
    • http://cetinelektrik.com.tr/wp-content/plugins/formcraft/file-upload/server/content/files/1606c840c69968---17229241046.pdf
    • http://www.hkqi.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608f4f5b0bcc1---semuvazedujudoted.pdf
    • https://completecollegestrategies.com/wp-content/plugins/super-forms/uploads/php/files/940cfee165d40d9a765ae113b58a0e6f/82290237926.pdf
    • http://ahkjt.com/upfile/file/jewemuzulosugasiloki.pdf
    • http://www.moteco.ro/wp-content/plugins/formcraft/file-upload/server/content/files/16097b7602ddf7---tadomoporaroluwaz.pdf
    • https://awlights.com/wp-content/plugins/super-forms/uploads/php/files/4c4adb2f3cc32b6f8e63c734d9705052/51622855422.pdf
    • https://feedproxy.google.com/~r/Uplcv/~3/zMnd8XtcwSM/uplcv?utm_term=write+the+plural+form+of+box
    • 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_off0000cf40.bin
a2614b81f6da8ea8cac2ccba4affff1d127c43c9e474d99be4ccd033582ecd17
pdf-font-stream PDF embedded font (sfnt) at offset 0xCF40 17300 bytes
font_01_sfnt_off0000fbfc.bin
c9345046cf6a34be76601735893678fb3acf7ae43a155e6bb462ef57951368ec
pdf-font-stream PDF embedded font (sfnt) at offset 0xFBFC 10684 bytes
font_02_sfnt_off00011441.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11441 16792 bytes