Malicious PDF — malware analysis report

Static analysis result for SHA-256 b7489648821e5f39…

MALICIOUS

PDF

75.8 KB Created: 2021-09-17 12:10:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-23
MD5: 32e7f15b82342f551055e02937b2685e SHA-1: 557ad21e740c6f13870a829f94eb60bd26fbaaba SHA-256: b7489648821e5f39e50596d285dc1a55a93070009f55649e6c3fd55870ca2af9
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous external links, many pointing to compromised CMS upload directories or disposable hosting, suggesting a link farm designed to redirect users. The ML classifier and ClamAV detection strongly indicate malicious intent, likely for phishing or malware delivery. Although no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with techniques used to host malicious content or redirect to phishing pages.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9973

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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://laborke.ru/uplcv?utm_term=kingdom+hearts+3+apk+download PDF link annotation
    • https://divinenine.net/userfiles/file/74407628532.pdfIn PDF document text
    • https://www.bouwenaaneensterkwerkgeversmerk.nl/wp-content/plugins/formcraft/file-upload/server/content/files/1612ea3f3abd5b---vegobixezifegotebilemiloz.pdfIn PDF document text
    • http://cortocircuito.trialpanel.com/images/Upload/files/92365732526.pdfIn PDF document text
    • https://www.tzounakos-insurance.gr/ckfinder/userfiles/files/raxalowuzubunifiberisuta.pdfIn PDF document text
    • https://gkatsov.com/userfiles/file/78455931553.pdfIn PDF document text
    • http://villaturri.com/wp-content/plugins/formcraft/file-upload/server/content/files/1614075c7175f9---42754474012.pdfIn PDF document text
    • http://chiangmai-clean.com/user_img/files/18569993502.pdfIn PDF document text
    • https://viveironativodevicosa.com.br/ckfinder/userfiles/files/43579316897.pdfIn PDF document text
    • http://innova-perila.ru/upload/files/zukoruberigemefo.pdfIn PDF document text
    • https://0900107678.com/upload/file/70127386871.pdfIn PDF document text
    • https://glamweddingdesign.com/userfiles/file/79185818096.pdfIn PDF document text
    • http://www.aamuhsv-madisonalumni.org/files/files/kewijolutigeza.pdfIn PDF document text
    • https://keralatemples.info/ckfinder/userfiles/files/95960390307.pdfIn PDF document text
    • http://autoscuolapezzano.it/userfiles/files/xetevapezorukujo.pdfIn PDF document text
    • http://tungalag.mn/userfiles/files/71051000417.pdfIn PDF document text
    • http://www.mostenpo.jp/userfiles/files/8600247411.pdfIn PDF document text
    • https://hoangmailogistics.com/asset/site/files/zorori.pdfIn PDF document text
    • http://dailythang.com/userfiles/files/26511454776.pdfIn PDF document text
    • http://ckm-machinery.com/userfiles/files/83821082113.pdfIn PDF document text
    • http://ylpqzl.com/ckfinder/userfiles/files/97009062354.pdfIn PDF document text
    • https://claudiodituri.it/uploads/gosafoj.pdfIn PDF document text
    • http://master-br.ru/img/file/vubatijowuforulodusupek.pdfIn PDF document text
    • https://tuabogadoangel.com/wp-content/plugins/super-forms/uploads/php/files/25e6b7ca45252576d4632f425720793c/lotoxikazedipadelujaxefe.pdfIn PDF document text
    • http://futboltotal.net/images/files/62682801022.pdfIn PDF document text
    • http://aktifbant.com/resimler/files/rizagufapese.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_off0000c1f8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC1F8 17568 bytes
SHA-256: 7758d5fd17b3df06bbce0d2a6a683693e3c1bd3b460ae9261ab3d80f695d933f
font_01_sfnt_off0000ef59.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEF59 11180 bytes
SHA-256: c15508f5c6016e9c3b4964345c85fcdb587398b92328abe7ae9e7856a0f8e743
font_02_sfnt_off00010928.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10928 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1