Malicious PDF — malware analysis report

Static analysis result for SHA-256 7d5efa632c7ab383…

MALICIOUS

PDF

83.6 KB Created: 2021-08-29 05:13:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 8d1aa306e8b54b23bb73fa47c4065dff SHA-1: 355b59ce0aecc703a4c09a7372d9198b18ce49ad SHA-256: 7d5efa632c7ab38335269967b4a16a09742c7be8ece582126474535f1c79dee9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to compromised CMS upload directories or disposable hosting, indicating a link farm designed to distribute malicious content. The ML classifier and ClamAV detection strongly suggest malicious intent, likely related to phishing or malware delivery. While no scripts were directly extracted, the nature of the URLs and the heuristic firings point towards a spearphishing attachment attack vector.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 https://sokolzgierz.pl/web/uploads/files/83122894162.pdf
    • https://123kozijnofferte.nl/wp-content/plugins/super-forms/uploads/php/files/v39udhjn8jrgv514r51l9cfla6/vetikulep.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ba5f2c2ba67---17823521407.pdf
    • http://thaiboxes.com/piceditor/file/fabijowatiwor.pdf
    • https://cengilli.com/icerik_images/file/pitomomaxepusivesuzuto.pdf
    • http://circuitvietnamcambodge.com/hinhanh/file/78836453980.pdf
    • https://earplighting.com/wp-content/plugins/super-forms/uploads/php/files/ae1b5d22114c582923b5c4fde0c8acfd/68453700888.pdf
    • https://pmeds.us/userfiles/file/31375124935.pdf
    • https://fertilizergranulatorprice.com/d/files/lezasumiwaxufabotok.pdf
    • https://terminarz.online/kosmetyczka/krakow/files/nogoderonimijinesotenulud.pdf
    • https://ceral.pl/ceral/pliki/file/81123555127.pdf
    • http://www.lightingandhvacexpo.com/wp-content/plugins/super-forms/uploads/php/files/c0029877a21a7c978fa1f19e77929ed0/8724548735.pdf
    • http://eunlocker.com/Images/Editor/file/79650553334.pdf
    • http://nakamurasangyou.jp/app/webroot/uploads/files/lozopovate.pdf
    • http://gabortech.comadmin/file/pisegiwijagejunaf.pdf
    • https://topinsolventa.ro/userfiles/file/wofisezusafinonon.pdf
    • http://thaihotelsale.com/FileData/ckfinder/files/20210606_3906F2D74C6A6CD7.pdf
    • http://world-green-hope.com/uploads/files/sifogimuduboxoditeji.pdf
    • http://songhakbbq.com/uploads/files/17507855284.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/37420f16187cee95fbf1fb095bef36c5/66399282814.pdf
    • https://bostoncake888.com/UserFiles/files/zugekelefuzon.pdf
    • https://rimsball.com/ckfinder/userfiles/files/begodaza.pdf
    • http://xn--2vxr09c6mc.tw/CKEdit/upload/files/99276084166.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/1xuhb7AK25c/uplcv?utm_term=pdf+of+biology+class+11+chapter+1
    • 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_off0000de68.bin
175170c1932a68dd803567945bb9d0db01fa199bb9f374fbdc3078f6a7d0a2b0
pdf-font-stream PDF embedded font (sfnt) at offset 0xDE68 18424 bytes
font_01_sfnt_off00010e4c.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10E4C 16792 bytes
font_02_sfnt_off00012663.bin
5ebc102304262678adc2188b07fbc8a839914d31fa2e806ed5ea636bc8004bb1
pdf-font-stream PDF embedded font (sfnt) at offset 0x12663 11104 bytes