Malicious PDF — malware analysis report

Static analysis result for SHA-256 525952fac5cba153…

MALICIOUS

PDF

89.4 KB Created: 2021-09-16 06:09:45 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-24
MD5: 8eda5d3b69d9f11e55339d52240b4f15 SHA-1: 303b26884abd4cfc6352c9883987e8f1f947c1ab SHA-256: 525952fac5cba153dafe7eef957304b7e8191ea9af9f006db711be2c9758fbd5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF file contains numerous embedded URLs pointing to various domains, many of which appear to be compromised CMS upload directories or disposable hosting. The ML classifier strongly indicated maliciousness, and the heuristic firings confirm the presence of a link farm designed to redirect users. No scripts were extracted, but the primary function appears to be redirecting users to external, potentially malicious, content.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9913

Heuristics 5

  • 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://medvor.ru/uplcv?utm_term=demon+slayer+movie+release+usa PDF link annotation
    • http://mgrima.com/files/file/27867175942.pdfIn PDF document text
    • https://autosofortkauf.ch/wp-content/plugins/super-forms/uploads/php/files/jq2spk6uv3off07ucmtfhdn48r/bosevakugub.pdfIn PDF document text
    • http://goldcoil.com/uploadfiles/files/9885407323.pdfIn PDF document text
    • https://www.goldenplanet.dk/wp-content/plugins/formcraft/file-upload/server/content/files/1613f3c814ee6a---75192550143.pdfIn PDF document text
    • http://xn----7sbab1bcaqplb0ccyi9d.xn--p1ai/files/file/lujawagalokalakulop.pdfIn PDF document text
    • http://www.gdchgs.com/admin/img/files/51279325469.pdfIn PDF document text
    • http://albino-pitti.com/pub_img/file/49850471108.pdfIn PDF document text
    • https://danfort.lv/userfiles/file/13862646177.pdfIn PDF document text
    • http://gaziogluenerji.com/images_upload/files/mexamofawi.pdfIn PDF document text
    • http://sgo-bage.com/public/files/files/71554964893.pdfIn PDF document text
    • http://hizirferforje.com/admin/fckeditor/editor/images/file/suxefopavozige.pdfIn PDF document text
    • https://mkart.it/uploads/file/41659393008.pdfIn PDF document text
    • http://vodnik48.ru/content/file/61344485228.pdfIn PDF document text
    • http://flapboxes.custompackageboxes.com/userfiles/files/falebulefuxaxalewo.pdfIn PDF document text
    • http://anthonyjcincottalaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/86872315779.pdfIn PDF document text
    • http://huyminhplastic.com/upload/files/jozomogitalufozibisido.pdfIn PDF document text
    • https://saigonservices.vn/images/uploads/files/10519642446.pdfIn PDF document text
    • https://gamedunyasi.com/calisma2/files/uploads/keremufadisujos.pdfIn PDF document text
    • https://skillmapmagazine.com/ckfinder/userfiles/files/60685055238.pdfIn PDF document text
    • https://mmszke.hu/files/file/dagupigarivabepan.pdfIn PDF document text
    • http://jeyadhurgatemple.com/userfiles/file/kifizinowukiwafor.pdfIn PDF document text
    • http://www.miwon.vn/app/webroot/uploads/files/5838150687.pdfIn PDF document text
    • http://yibetter.com/data/files/11698889840.pdfIn PDF document text
    • https://neoville.ru/wp-content/plugins/super-forms/uploads/php/files/1735ad128559b1c0984fca908eb8df1f/54737689846.pdfIn PDF document text
    • http://lor-rostov.su/userfiles/files/besotijenubule.pdfIn PDF document text
    • https://bulgariapools.com/contents/files/53877508524.pdfIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e894.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE894 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_01_sfnt_off000100ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x100AB 10452 bytes
SHA-256: c99d9591a5cb0bd232661650c25b19ecb339dc86d06a280f6038cc9ea2f77f1d
font_02_sfnt_off0001185e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1185E 24012 bytes
SHA-256: 1d3cdb484611666ed93e4ab2bd1a7c529bfb725a1975441819008c24a5b68912