Malicious PDF — malware analysis report

Static analysis result for SHA-256 b31be646830454c9…

MALICIOUS

PDF

84.5 KB Created: 2021-09-13 08:52:30 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 9a15dd928100455cb67e457170728826 SHA-1: 3415fc508654a2be6d3ffc76689bc51e6a69eaf1 SHA-256: b31be646830454c9edb65a707347037075250bab79aaa13542d09db311ef5c07
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF file was flagged by a machine learning classifier and ClamAV as malicious, specifically as a phishing trojan. Heuristics indicate it functions as a link farm, directing users to various domains, some of which are hosted on compromised WordPress sites or disposable hosting. The presence of a 'download button' lure further supports a phishing or malware distribution attempt.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9951

Heuristics 7

  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://oniceh.ru/uplcv?utm_term=abcd+full+movie+download+720p
    • https://luatsubienhoa.com/upload/ck/files/45862360286.pdf
    • http://locthanhroyal.com/upload/files/74350135806.pdf
    • http://adacu.org/userfiles/file/20210906160923.pdf
    • https://valubil.com/public/uploads/cms_file/cms_files/laneruguwobutabexofavixav.pdf
    • http://cuanhomkinhtoanthang.com/media/file/newopunijafagapibitoke.pdf
    • https://vildmarksjagt.dk/userfiles/file/71983640336.pdf
    • https://childprotectionindia.com/lexcyberia/userfiles/files/fazukamivaza.pdf
    • http://banlinhkienlaptop.com/userfiles/file/xoxepij.pdf
    • https://jetaime-shop.dvsportbg.com/files/150850628.pdf
    • http://toyotaquangninh.org/data/dulieu/files/megijuxoporogapodetidul.pdf
    • https://sunridgecorp.com/uploads/files/202109081936354273.pdf
    • http://dorisemitchell.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/fijuxasisanunajubawel.pdf
    • http://securitydirect.it/wp-content/plugins/super-forms/uploads/php/files/2b05418a15b756491ddc73640ffe715a/tiwiluniwesepotilovakem.pdf
    • http://fisioterapiasuzzara.it/userfiles/files/zotezezoxido.pdf
    • http://shtaket46.ru/page_edit/_samples/userfiles/files/30493732633.pdf
    • https://www.financedeclined.com.au/wp-content/plugins/formcraft/file-upload/server/content/files/161324aa65dcf2---58218413294.pdf
    • https://ppntassone.it/dati/upload/file/vutinusanutovegunufo.pdf
    • http://bobas24.pl/Upload/file/48514229809.pdf
    • http://7m-shop.com/userfiles/file/80604018983.pdf
    • http://e-sportis.com/images/upload/25462342247.pdf
    • https://rakowka.pl/userfiles/file/vozawemobejajipixedusex.pdf
    • https://zohopinler.com/calisma2/files/uploads/kirilidizakukeveloxonob.pdf
    • https://lashmakerpro.it/wp-content/plugins/super-forms/uploads/php/files/c16qj3cirtr28vlaav5et9ish2/64233640863.pdf
    • https://mandalaconfeccao.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1613b1d1f082b1---fisezajukaninofoxipapex.pdf
    • http://naturestuff.nl/siteimages/file/74252925421.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_off0000e5b6.bin
d4c43cd48d1d0d215f8ac89561cff9ac1798dfb454a5ffae5b1793bb09882ea0
pdf-font-stream PDF embedded font (sfnt) at offset 0xE5B6 11080 bytes
font_01_sfnt_off0000ff75.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFF75 16792 bytes
font_02_sfnt_off00011787.bin
a775f988523cc6501c18976434b3464e4b0c0810602b991f8975481afe27b85b
pdf-font-stream PDF embedded font (sfnt) at offset 0x11787 17256 bytes