Malicious PDF — malware analysis report

Static analysis result for SHA-256 01fef6e0c8c2dba9…

MALICIOUS

PDF

86.8 KB Created: 2021-09-17 13:31:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: da1007d79010a6fd4a11fc40c6fad274 SHA-1: 9b8f9970dddffd39c27c3ea19cd7acd2cc2c2d51 SHA-256: 01fef6e0c8c2dba98ce055e5acb85ef1850cece096c06edceaf78309ba5f1890
164 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains embedded JavaScript and is flagged as malicious by ML classifiers and ClamAV. It also exhibits characteristics of a link farm, pointing to multiple external URLs, some hosted on compromised CMS platforms. The embedded JavaScript likely facilitates the redirection to these external sites, which are used to host further malicious content or phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

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.
  • Embedded JS stream low PDF_JS
    PDF references a /JS stream. Generic JavaScript is common in benign forms; specific dangerous APIs are scored by separate rules.
  • 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://ctyrkolky-gamax.cz/data/dokumenty/fuburowiginomisokezupa.pdf
    • https://wonwon.taipei/photo/file/dobipizimo.pdf
    • http://huabulaw.com/uploadpic/2021-9/file/2021090716563373499.pdf
    • https://gagiongvitgiong.com/ckfinder/userfiles/files/deduzaf.pdf
    • http://park-seversk.ru/other/js/ckfinder/userfiles/files/kidogoka.pdf
    • https://superchills.com/userfiles/file/dumebun.pdf
    • https://atvatextile.com/upload/ckfinder/files/sumupa.pdf
    • https://strategieb2b.ca/userfiles/file/82925022669.pdf
    • http://ride.hu/images/uploads/files/xenanisasil.pdf
    • http://bangkokmagnetwire.com/ecodev_test/image_system/files/tiseregedubujiguxokuf.pdf
    • https://bulgariapools.com/contents/files/90931420540.pdf
    • http://corising.info/sa_upload/userfiles/file/20210913134435.pdf
    • https://ketgate.eu/wp-content/plugins/super-forms/uploads/php/files/188113d32b0f42f13685b94441011219/kazisakenen.pdf
    • https://carparts-fixture.com/file/file/48792394082.pdf
    • http://sporteambiente.it/ckfinder/userfiles/files/zuguserevaketof.pdf
    • http://xn--b1amishc2fb.xn--p1ai/ckfinder/userfiles/files/13742227854.pdf
    • http://kameleonhastanc.hu/files/file/razatobuzafalifivut.pdf
    • https://popcouncilinstitute.org/wp-content/plugins/super-forms/uploads/php/files/6ef3c58abb80e602603112f4d517739a/80382586995.pdf
    • http://www.barbazan-debat.fr/ckfinder/userfiles/files/83954373405.pdf
    • http://hwayoung.kr/upfile/files/sifunatagekururugowug.pdf
    • https://felicityokolo.com/file/49917686351.pdf
    • http://prvugkh.ru/uploads/files/3091935822.pdf
    • http://ntouioc.ntou.edu.tw/ckfinder/userfiles/files/dewikurobozoxika.pdf
    • http://nek.ua/wp-content/plugins/formcraft/file-upload/server/content/files/16130fa68e1c2d---varowalupudijeben.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/3vuEKuznOb8/uplcv?utm_term=minecraft+server+list+android
    • 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_off0000ebd8.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEBD8 16792 bytes
font_01_sfnt_off000103ef.bin
2d851220dacf8bc8f6d017c8fb7e135c5864948d08e8014c6ab1881d536bbb70
pdf-font-stream PDF embedded font (sfnt) at offset 0x103EF 10528 bytes
font_02_sfnt_off00011c11.bin
8448afee89c0580890bbd1b138e71d36be23f36ae4dadcebbb508d7c135ba7f0
pdf-font-stream PDF embedded font (sfnt) at offset 0x11C11 19120 bytes