Malicious PDF — malware analysis report

Static analysis result for SHA-256 aac5fe109f4a0acc…

MALICIOUS

PDF

83.3 KB Created: 2021-08-03 13:46:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-10-04
MD5: c0ba4517dd50d2de54a44b9f5f10deaa SHA-1: 0b8987a9173a30abe055ab60774bc348c94de1d5 SHA-256: aac5fe109f4a0acca63f95ad34b9bed360ca0e2079d084dff4ae72927f104efe
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF document was flagged as malicious by ClamAV and an ML classifier. The file embeds a large number of external links characteristic of an SEO link farm, many hosted on compromised CMS upload directories. Specific URLs and indicators for this sample are listed in the indicators section.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9995

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://ketchas.ru/uplcv?utm_term=ib+biology+course+book+oxford+ib+diploma+programme+2014+pdf PDF link annotation
    • http://mirembeestate.co.ug/wp-content/plugins/formcraft/file-upload/server/content/files/16079985da053e---59278740273.pdfIn PDF document text
    • http://airholic.com/UpFiles/WebEditorFiles/file/rerezovozuxogoxarotajuja.pdfIn PDF document text
    • http://drvision.org/wp-content/plugins/formcraft/file-upload/server/content/files/160bddfcc5a569---xunowetijibunisofe.pdfIn PDF document text
    • http://www.naturapreserved.com/wp-content/plugins/formcraft/file-upload/server/content/files/160c16f4e02f40---14245786004.pdfIn PDF document text
    • https://kovosluzba-praha.cz/res/file/wodaluloz.pdfIn PDF document text
    • https://xuanhongkhang.com/upload/files/15542701617.pdfIn PDF document text
    • http://ozkayalartrans.com/userfiles/file/55860178672.pdfIn PDF document text
    • https://kltccompany.com/ckfinder/userfiles/files/48248779471.pdfIn PDF document text
    • http://www.kevinbrooks.ca/wp-content/plugins/formcraft/file-upload/server/content/files/160f724d405fe9---kumero.pdfIn PDF document text
    • http://aa-nusd.jp/wofilakizabikugu.pdfIn PDF document text
    • http://hephatha100.com/clients/4/45/452f9a9cd3514f90eb92b3b4734a1f1d/File/50586238522.pdfIn PDF document text
    • http://sdds.be/userfiles/file/zetujoze.pdfIn PDF document text
    • http://sergey-yushkov.com/pict/file/kupirigal.pdfIn PDF document text
    • https://sipsib.ru/wp-content/plugins/super-forms/uploads/php/files/d5f89d318a612eff4400454636687c19/tipaxojijezuware.pdfIn PDF document text
    • https://cal.lighting/wp-content/plugins/super-forms/uploads/php/files/cd4ca649575a33d9c2da1c6a7d3d58d9/86167807422.pdfIn PDF document text
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/4980hkgvv96r4v4l1c8jspi1i3/baninugajirojidowabafiv.pdfIn PDF document text
    • https://tese.in/ckfinder/userfiles/files/32972688970.pdfIn PDF document text
    • http://mq-water.net/upload/17206316724.pdfIn PDF document text
    • http://alexlunacoach.com/img/editor/file/wevekebeg.pdfIn PDF document text
    • http://daeryuhealthcare.com/ckupload/files/kinifoxo.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 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000c8d9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC8D9 16944 bytes
SHA-256: 87baca9c006332ea7dacef7f774269cd9fabc750fbe4c5fad1bed81a7f38d91c
font_01_sfnt_off0000f52e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF52E 11632 bytes
SHA-256: b22f6d70d2a5decb773857b5572745ba5f15946cfb2261a9ae9d098da312fa00
font_02_sfnt_off0001109b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1109B 16152 bytes
SHA-256: a296b1387adcec6f3b2576628ea92b3d2a56d809f0e877613436961f86b2f7ca
font_03_sfnt_off00012623.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x12623 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1