Malicious PDF — malware analysis report

Static analysis result for SHA-256 88cbccfe945d7599…

MALICIOUS

PDF

68.4 KB Created: 2021-09-25 08:20:14 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: dcdf37cf9ef212a44379300dc98611b2 SHA-1: 8228545297ddb30ea08477ffb76ad2e52cb49382 SHA-256: 88cbccfe945d7599dd5becdf9cbb20cbaa67fe22e24e36187492fb03f4ae01ff
176 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF is identified as a phishing lure due to its image-only nature and embedded clickable links. The document contains numerous external URIs, many hosted on compromised or disposable domains, suggesting an attempt to redirect users to malicious sites. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for credential harvesting or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9954

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
  • Image-only document with action trigger (screenshot lure) medium PDF_IMAGE_LURE
    PDF has 1 image(s), only 0 text block(s), carries a click-outward action, and is only 68 KB — typical shape of a phishing lure where a full-page screenshot hides a clickable button that launches or submits to an attacker URL.
  • 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://synerhu.ru/uplcv?utm_term=sims+4+free+no+human+verification+android
    • https://armour-technoz-ca.otzol.net/ckfinder/userfiles/files/vefanamugegusosej.pdf
    • http://lnv-cnc.com/userfiles/file/78234335450.pdf
    • http://letnipohar.cz/upload/file/labazumajexulozuviruw.pdf
    • http://directopinion.biz/uploads/FCK_files/file/nobamonewixoba.pdf
    • http://hzzxtl.com/UploadFile/file/20210914010234728.pdf
    • http://quiltingacademy.net/fckeditor/userfiles/file/59062879445.pdf
    • http://machin.kr/userData/board/file/79217142925.pdf
    • http://www.webtony.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/1614cc389f0192---33052952675.pdf
    • http://automotiveenergy.cz/userfiles/file/ginobobewizibunadupebosek.pdf
    • http://giasuthanhdat.vn/Images_upload/files/2998637237.pdf
    • https://mgogs.com/mgfiles/file/47726031745.pdf
    • https://www.taxiserviceh24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1613fb19b96af9---89123040441.pdf
    • http://almawred-sy.com/files/adminfiles/files/11102400797.pdf
    • https://festivaldelmaridaje.com/sgi_userfiles/userfiles/files/57115954494.pdf
    • https://kawanmto.com/contents/files/runinetasudadodogupif.pdf
    • https://slavica.ru/wp-content/plugins/super-forms/uploads/php/files/dd79cd2519d0e8c90f8c7dedd659e89d/xegijuvoleri.pdf
    • https://asztromiskolc.hu/ckfinder/userfiles/files/dorajotarafasukosubiz.pdf
    • https://2ruoteexpo.it/ckfinder/userfiles/files/sajolajirupidobuwaxe.pdf
    • http://worldofpacifiers.com/editor_uploads/system/files/sasabedujizinupavararo.pdf
    • http://umrllc.com/userfiles/files/foxawoginirivugibuxape.pdf
    • https://arerp.kr/data/file///87104160255.pdf
    • http://slovoveri.org/userfiles/34116509457.pdf
    • http://image.dlib.vn/libedu/news/bachviet/20210923/file/zizaledavu.pdf
    • https://udachi.co.th/wp-content/plugins/super-forms/uploads/php/files/ca24q69p48kr5t70rko696o2sg/73076775861.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_off0000ae39.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xAE39 16792 bytes
font_01_sfnt_off0000c650.bin
79959c902bf580405a01803620ecff0fb5a6807f4bcfe85916230625b8e00caf
pdf-font-stream PDF embedded font (sfnt) at offset 0xC650 11012 bytes
font_02_sfnt_off0000dfc5.bin
2dd4e1c11792c5bca7139eeee7d524ea387c14902a461584ae5021a5fb5dfa3f
pdf-font-stream PDF embedded font (sfnt) at offset 0xDFC5 14064 bytes