Malicious PDF — malware analysis report

Static analysis result for SHA-256 17624857a313a498…

MALICIOUS

PDF

70.9 KB Created: 2021-10-01 05:26:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-26
MD5: 61c2b235765157d5b64270f820ef9e78 SHA-1: 9646b62bb953bf7725e3de6587c4626de0022820 SHA-256: 17624857a313a4989770ff46a2d308bc03a70dd6476531ee0f38a72002430a59
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains numerous embedded URLs, many of which point to compromised websites or disposable hosting, indicating a link farm designed to redirect users. The ClamAV detection and ML classifier strongly suggest malicious intent, likely phishing or malware distribution. No scripts were extracted, and the document body was unreadable, so the primary attack vector appears to be the embedded links.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9982

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://chcial.ru/uplcv?utm_term=walking+dead+season+10+episode+11 PDF link annotation
    • https://bhiringisamsankalimandir.org/ckfinder/userfiles/files/17302307329.pdfIn PDF document text
    • http://lnhaihui.com/userfiles/file/20210912211835_1352416052.pdfIn PDF document text
    • http://smithmurdock.com/wp-content/plugins/formcraft/file-upload/server/content/files/161379e1bf01ac---raxologezololigenaviw.pdfIn PDF document text
    • https://harom.ro/files/file/23110533917.pdfIn PDF document text
    • http://nwatchonline.org/userfiles/file/mikud.pdfIn PDF document text
    • https://www.lenoir-elec.com/wp-content/plugins/super-forms/uploads/php/files/lv3kvn9majj3msva3rb0va3feg/80389587337.pdfIn PDF document text
    • https://bisleri.genefied.co/ckfinder/userfiles/files/40889692462.pdfIn PDF document text
    • https://safarekhoob.ir/basefile/safarekhoobir/files/tanimujinag.pdfIn PDF document text
    • http://www.bash.cl/media/file/lixukofej.pdfIn PDF document text
    • http://fygl.net/uploads/file/060436177594.pdfIn PDF document text
    • https://laurallo.com/ckfinder/userfiles/files/piviwabezaji.pdfIn PDF document text
    • https://artinterior.bg/userfiles/file/rojuvix.pdfIn PDF document text
    • http://apple888.vn/luutru/files/71648831284.pdfIn PDF document text
    • http://dossalas.com/wp-content/plugins/super-forms/uploads/php/files/67d8a58a35307415308fa86433aad192/923714387.pdfIn PDF document text
    • http://basaritarim.net/admin/editor_resim/file/vidiluwomonodamimudeg.pdfIn PDF document text
    • https://www.cir.cloud/wp-content/plugins/formcraft/file-upload/server/content/files/1614d29f4165ae---63668626100.pdfIn PDF document text
    • http://www.fattyweng.com.sg/wp-content/plugins/formcraft/file-upload/server/content/files/1614b0eab572b2---57755816539.pdfIn PDF document text
    • https://kurek-rowery.pl/user_pict/file/738188414.pdfIn PDF document text
    • http://mzch.pl/userfiles/file/pesozodezimomogorewir.pdfIn PDF document text
    • http://www.perlodrink.com/documents/xasowudadelasiga.pdfIn PDF document text
    • http://chonburi33.com/userfiles/file/vupopu.pdfIn PDF document text
    • http://bjxbw.cn/userfiles/file/3342099502.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_off0000b2a8.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xB2A8 16796 bytes
SHA-256: 1f8adeba7755c54eb7146fb4cc0fef3d1043b5d1d89ccf13253f73b4e30701b1
font_01_sfnt_off0000dda6.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xDDA6 10628 bytes
SHA-256: 24300edfc1239c6d4b488e907ac596fc11c52fa2caea3f6265884bd7e7f4bce6
font_02_sfnt_off0000f5da.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF5DA 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1