Malicious PDF — malware analysis report

Static analysis result for SHA-256 8d7ea985e2995343…

MALICIOUS

PDF

89.7 KB Created: 2021-06-24 10:55:42 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-13
MD5: 567a2f8d7762199205500f80d4971888 SHA-1: 001e863e63649d8544304e54a93b857cfe1e005f SHA-256: 8d7ea985e2995343ba338bf96f5723f447f10c6f7a90456d5276dff55e1906b3
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF document is identified as malicious by an ML classifier and contains numerous external links, many pointing to compromised CMS upload directories. The document body, though heavily obfuscated, suggests a lure related to 'headway intermediate workbook answer key fourth edition', indicating a likely phishing or malware distribution attempt. No scripts were extracted, but the presence of multiple external links and the ML classification strongly suggest malicious intent.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9992

Heuristics 5

  • 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://pixomot.ru/uplcv?utm_term=headway+intermediate+workbook+answer+key+fourth+edition PDF link annotation
    • http://yishiweb.com/upfiles/files/20210616_224632.pdfIn PDF document text
    • http://dralituncer.net/userfiles/file/11260490600.pdfIn PDF document text
    • http://temple.mo/userfiles/file/danegosifowe.pdfIn PDF document text
    • https://www.temsilcifirsatlari.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607865c4dc213---daxelowexe.pdfIn PDF document text
    • http://www.inhd.com.br/wp-content/plugins/formcraft/file-upload/server/content/files/160b03512eb752---legimizufawenefu.pdfIn PDF document text
    • http://theydeserveastamp.org/wp-content/plugins/formcraft/file-upload/server/content/files/1607c4be711b8e---38069036659.pdfIn PDF document text
    • https://vandolderskb.com/images/usr/sogulozebanaxivijulatuxa.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/7715daa610a7872770370668e89be3f7/nadalavanalarozakov.pdfIn PDF document text
    • http://mwflower.com/upimagesfile/%5C/36745799810.pdfIn PDF document text
    • https://teenvolunteerdallas.org/wp-content/plugins/super-forms/uploads/php/files/e4de5b7a35fd3e0d083cd280bdd82ffb/6543908515.pdfIn PDF document text
    • http://archimax.ch/dynamic-images/cms/file/31906161089.pdfIn PDF document text
    • https://earthideasawnings.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607f3af98a09c---kabijofe.pdfIn PDF document text
    • http://auto-spec.ca/fck/file/ravemepuwagodumigawizo.pdfIn PDF document text
    • http://www.investing-in-women.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608c21c881636---76852195003.pdfIn PDF document text
    • http://aarogyamedico.com/userfiles/file/vunofaxelekoniwujuderabol.pdfIn PDF document text
    • http://automotiveenergy.cz/userfiles/file/63016258826.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn 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://scripts.sil.org/OFLIn PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.orgIn PDF document text

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e247.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xE247 3620 bytes
SHA-256: 05a6f1f870c55f4cdaf2a11a575834d8284c8feb9153d18a4b25b0b3446b0fcb
font_01_sfnt_off0000eef0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xEEF0 5472 bytes
SHA-256: 0cb37a0cdd2a991057cf09d61a535880255505e24d626d63917f320f3f1a8b94
font_02_sfnt_off00010175.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10175 16904 bytes
SHA-256: ec8cf0b676aaab1828e055523b679d89d27dbc83386e4b8c17a57f29868214b9
font_03_sfnt_off0001331c.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x1331C 16156 bytes
SHA-256: e94d9fa8b23aa0827f5bd97b41e450e4c70ec8cd881880446398b13205f313c9
font_04_sfnt_off00014853.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x14853 5932 bytes
SHA-256: 625d85dba123278efa1bc63533ad5030011f966b9adecc893c3d63e9d9dfe5b1