Malicious PDF — malware analysis report

Static analysis result for SHA-256 c5759da7f8b7588e…

MALICIOUS

PDF

58.3 KB Created: 2020-10-02 17:49:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-23
MD5: ed95adcea065934d66dfc70a153ffed6 SHA-1: 0e82c762c06e92b5df0c915ef3dd500ba621230f SHA-256: c5759da7f8b7588e92bfd334b644fba0617048058a1b4d0d29f6080c4c09fb9a
184 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, many of which point to disposable hosting and redirect to malicious infrastructure, as indicated by the 'PDF_MALICIOUS_REDIRECTOR_LINK' and 'PDF_SEO_LINK_FARM' heuristics. The document body, though heavily obfuscated, contains a URL that matches the malicious redirector, suggesting an attempt to drive traffic to malicious sites. The ML classifier also strongly flagged this PDF as malicious.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 5

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • 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.
  • 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://cctraff.ru/strik?keyword=audi+r8+manual+conversion In PDF document text
    • http://files.fabiolapiedadmariaalicia.com/uploads/1/3/1/4/131437444/pujisojeton-vadenuvemamul.pdfIn PDF document text
    • http://goleji.annawitte.org/uploads/1/3/0/7/130776367/48aa61.pdfIn PDF document text
    • http://files.akalasjewelry.com/uploads/1/3/0/7/130740530/5283910.pdfIn PDF document text
    • http://varevaba.norwellgiving.com/uploads/1/3/1/1/131163857/7319509.pdfIn PDF document text
    • http://redezose.premierpropertysvc.com/uploads/1/3/2/6/132695278/nutiragojufiguw_gatowo_bevimuzijewinen_sozonazopisi.pdfIn PDF document text
    • https://site-1038558.mozfiles.com/files/1038558/36052498239.pdfIn PDF document text
    • https://site-1036811.mozfiles.com/files/1036811/25506520114.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://uploads.strikinglycdn.com/files/f21a3fae-dc42-4e0a-bbb9-778a66bcd8f4/tomidupamifenunavad.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/0e9d1dc6-4ef0-41fb-865e-b88c879142f9/30154474894.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4962ec8f-1db8-4c07-8b36-26171041a5f5/36530870469.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/4c6ad73b-f559-49d2-b404-53c6ecb78c75/43306712144.pdfIn PDF document text
    • https://uploads.strikinglycdn.com/files/837d6fb6-6adc-43e0-acfc-f7b13c7ddb79/sovazina.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/4567/4389/files/generate_signed_apk_android_studio.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0497/3779/3697/files/1618379412.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
    • https://savannah.gnu.org/projects/freefont/In PDF document text
    • http://www.gnu.org/licenses/In PDF document text
    • http://www.gnu.org/copyleft/gpl.htmlIn 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

Extracted artifacts 5

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000068cf.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x68CF 6744 bytes
SHA-256: b29f9350a720d2da9dc50567d08c4a82684db1fcb28a47e3a5788345b392d808
font_01_sfnt_off000079b4.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x79B4 5328 bytes
SHA-256: 02e80373b6de759c6af3fc7c19930f6099f2d84fa4e8757bd76aa998e24bac7b
font_02_sfnt_off00008bb1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x8BB1 6296 bytes
SHA-256: e1dacd82965cdbd68fc3b806d699d1f1bb8c67e081b856d189fb1354055f2fc8
font_03_sfnt_off0000a0ab.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA0AB 11032 bytes
SHA-256: 8cde54508852fbdc861256fd0a73ad65f3361a84c7a0a705ef6b945ccb6019b3
font_04_sfnt_off0000c67d.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xC67D 16080 bytes
SHA-256: 4862f0796d5cbf2b429715f2b47f15d06f0c641f927a022d27f217f4f39910ad