Malicious PDF — malware analysis report

Static analysis result for SHA-256 1136aecb5e0fdde4…

MALICIOUS

PDF

80.3 KB Created: 2021-09-16 13:02:34 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3) First seen: 2021-09-27
MD5: b44976a8e78f00d0d5cf926b2e1d04c9 SHA-1: 661aa0f9e1ccd161ee37df8632d6d4c26cf7097e SHA-256: 1136aecb5e0fdde442547968d1d8aa4526a2da7f2f72fe68d823225ddd721e16
166 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF contains numerous embedded URLs, many of which point to potentially malicious content or are part of a link farm. The 'SE_PASSWORD_ARCHIVE_LURE' heuristic indicates the document likely instructs the user to decrypt a password-protected archive, a common tactic for evading gateway security. ClamAV detection and ML classification further support its malicious nature, suggesting it's a phishing or trojan delivery mechanism.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9953

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
  • Password-protected archive handoff high SE_PASSWORD_ARCHIVE_LURE
    Document gives password instructions for an archive or attachment — often used to keep payloads encrypted until after gateway scanning
  • 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://fuhua.tumujike.com/assets/upload/files/202109080125239820.pdf In PDF document text
    • http://www.ez4parcel.net/upfile/files/2021/09/05/58458501732.pdfIn PDF document text
    • http://inciboya.com/resimler/site/files/soropavisujititegone.pdfIn PDF document text
    • http://imdad-egypt.com/userfiles/file/40768861249.pdfIn PDF document text
    • https://hebatkeren88.com/contents/files/92879960726.pdfIn PDF document text
    • http://tokstar.com/_UploadFile/Images/file/96677864372.pdfIn PDF document text
    • http://okuninka-biale.pl/userfiles/file/18216076263.pdfIn PDF document text
    • https://ssmahavidyalaya.org/lion/uploadedfiles/fck/files/file/57790829255.pdfIn PDF document text
    • https://computerzone.pk/file/49017290256.pdfIn PDF document text
    • http://health-bridge.in/upload/file/kagire.pdfIn PDF document text
    • http://ainut.fi/userfiles/file/23036722187.pdfIn PDF document text
    • http://bakersfield.thepokeluau.com/uploads/files/99257656541.pdfIn PDF document text
    • https://elsa-daulte.com/ckfinder/userfiles/files/mopizabisoxepilalurekuxe.pdfIn PDF document text
    • http://majorpropertygroup.com/userfiles/files/18076209276.pdfIn PDF document text
    • https://proektasis.gr/admin/spaw2/uploads/files/kabikalizoraw.pdfIn PDF document text
    • http://modelseafarm.com/kweb/ckfinder/userfiles/files/32280584686.pdfIn PDF document text
    • http://stefani.cz/fck/file/6898626687.pdfIn PDF document text
    • https://sahyadrisevasanstha.in/userfiles/file/58373566630.pdfIn PDF document text
    • https://istanajp.net/contents/files/46760512557.pdfIn PDF document text
    • http://vizugy.hu/uploads/files/files/98924759229.pdfIn PDF document text
    • http://elverum-revmatiker.no/images/file/vogolunefovazubitowuxe.pdfIn PDF document text
    • https://www.jakketoes.be/ckfinder/userfiles/files/tevurugisebufenidenux.pdfIn PDF document text
    • https://officialbacknumber.org/editor_up/28697904100.pdfIn PDF document text
    • http://www.juniorcollege.cl/ckfinder/userfiles/files/jodixiveduzijabalawalune.pdfIn PDF document text
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/FevRqgeaUVY/uplcv?utm_term=zip+file+recovery+androidPDF 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_off0000d51a.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xD51A 10492 bytes
SHA-256: 1ba1cdc2a68cb8e3e6d406342e8bb3783e34e502dd896559b0742f651388165d
font_01_sfnt_off0000ed0d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xED0D 17908 bytes
SHA-256: a033b15dad89a853ef923be602ec275891b257f800f1049a9d2b972c55acc157
font_02_sfnt_off00011b98.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x11B98 16792 bytes
SHA-256: 9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1