Malicious PDF — malware analysis report

Static analysis result for SHA-256 68dab1946a8cb030…

MALICIOUS

PDF

88.3 KB Created: 2021-06-25 15:16:57 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-08-25
MD5: 1cde4134d3ae26aad9cdc5521b74822d SHA-1: 1b365a0e589757b166ac601bf67d6090aaf20858 SHA-256: 68dab1946a8cb0304f1882166cf8d432f079b8817ff0aaad23bfd7640bca7ff8
156 Risk Score

Malware Insights

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

The sample is a PDF file detected as malicious by ClamAV and an ML classifier. It contains numerous embedded URLs, many of which point to potentially compromised WordPress sites or disposable hosting, suggesting a link farm designed to redirect users. The heuristic 'PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM' indicates these links are likely part of a phishing or malware distribution scheme.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9991

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 http://anhuizhkj.com/upload_fck/file/2021-6-5/20210605194529259408.pdf In PDF document text
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/5v7j26hi2338i30ohnfs9ri943/pujudofefuga.pdfIn PDF document text
    • https://sg-design.top/wp-content/plugins/super-forms/uploads/php/files/4c865eb34003dbd0e28e78534cd100f5/688267430.pdfIn PDF document text
    • https://goldengrowers.com/wp-content/plugins/super-forms/uploads/php/files/ebdf2d34e7237c9d05029502d342f30b/ninenutowozasevibaruwuxel.pdfIn PDF document text
    • http://usarsenal.it/userfiles/files/dodufezebanigow.pdfIn PDF document text
    • https://dacoma.ro/wp-content/plugins/formcraft/file-upload/server/content/files/1606d1d9954acb---wodiwip.pdfIn PDF document text
    • http://tgtech-auto.com/userfiles/file/44164172951.pdfIn PDF document text
    • http://www.1atlanticfunding.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606dd9079441a---7001180244.pdfIn PDF document text
    • https://clubforeducation.com/FCKeditor/userfiles/file/tokobepalodutifedesoko.pdfIn PDF document text
    • http://yatros.ro/wp-content/plugins/formcraft/file-upload/server/content/files/160bdcc9db1195---vutedaxijizejilazexof.pdfIn PDF document text
    • https://kayakbranson.com/wp-content/plugins/formcraft/file-upload/server/content/files/16099dfee7f350---59720460083.pdfIn PDF document text
    • https://bangprice.combangprice.com/beta/cms_image/file/95065918602.pdfIn PDF document text
    • https://gamletaarnhuset.no/wp-content/plugins/formcraft/file-upload/server/content/files/16073c695d0809---16664729311.pdfIn PDF document text
    • https://cicadit.ro/UserFiles/file/natomuk.pdfIn PDF document text
    • https://rrvchefs.com/wp-content/plugins/super-forms/uploads/php/files/fbf8e2c1ed81ed40a0eff29c55f4aba5/sezeposixabumubi.pdfIn PDF document text
    • https://freedomtampons.com/wp-content/plugins/super-forms/uploads/php/files/7c1b5533be441e345a46cab9f59789bb/nowet.pdfIn PDF document text
    • https://feedproxy.google.com/~r/Uplcv/~3/fzgW7-mxBc0/uplcv?utm_term=221+boulder+ridge+road+scarsdale+nyPDF link annotation
    • 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_off0000f6cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF6CF 17216 bytes
SHA-256: 1bccc41cb5ef7698c09e24d658ee440cbdb689ebc5da7423dc8e89cc25f8c2cb
font_01_sfnt_off00012376.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12376 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
font_02_sfnt_off00013b8d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x13B8D 10876 bytes
SHA-256: f435214f896161979d67cd3e68c9b0086ebb1689806dd2e841e2e9d1e3caea03