Malicious PDF — malware analysis report

Static analysis result for SHA-256 43708fbde3106da6…

MALICIOUS

PDF

74.5 KB Created: 2021-03-13 18:22:46 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 9367816d45fa3a596fb35b4599878a72 SHA-1: 00d7109d41236137f8726ce8db2af1cd8a26fbc2 SHA-256: 43708fbde3106da63c5a7f3462505a23ee6b43efaebb7147ec8ee943ab583d7c
156 Risk Score

Malware Insights

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

The PDF contains numerous external links, with a critical heuristic identifying it as a PDF SEO link farm. One prominent external URI, 'https://vilenefex.ru/award?keyword=bio+plastic+pdf', is flagged as suspicious. The ML classifier and ClamAV detection strongly indicate malicious intent, likely related to phishing or distributing further malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9993

Heuristics 5

  • 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.
  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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://vilenefex.ru/award?keyword=bio+plastic+pdf
    • https://cdn-cms.f-static.net/uploads/4448343/normal_6011899f47948.pdf
    • https://cdn-cms.f-static.net/uploads/4393790/normal_5fd78cc3245f7.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://uploads.strikinglycdn.com/files/fb8e7cf7-8b35-460e-be03-e3e7d3ba29f9/lufufenosusazopegoxo.pdf
    • https://s3.amazonaws.com/rurovikejigibu/jokadirolepumakefuw.pdf
    • https://e5baaea7-7007-41de-9367-4ebf3ed55875.filesusr.com/ugd/8e1900_25b22d655e124a05bdbc27f4f42f68d5.pdf?index=true
    • https://s3.amazonaws.com/wonumafubij/95197381818.pdf
    • https://6346cca1-8be9-442e-91e0-e35201572fa6.filesusr.com/ugd/a8c077_c1602d6d6ab9490094220bb738777805.pdf?index=true
    • https://s3.amazonaws.com/batoragubukepo/bombay_stock_exchange_in_india.pdf
    • https://s3.amazonaws.com/pewebopufupe/kixasalotazoliwolajozad.pdf
    • https://uploads.strikinglycdn.com/files/158365eb-aac7-4275-8906-aad29bca27c5/90061009752.pdf
    • https://s3.amazonaws.com/sudevejerifu/goweden.pdf
    • https://s3.amazonaws.com/wonumafubij/70990414774.pdf
    • https://c31d65df-273c-4bcc-acfb-7b03b0724b99.filesusr.com/ugd/e7e4a0_9ab3e49fee194beda6b56129d01ca229.pdf?index=true
    • https://a24bc4ef-4ee2-4fae-af0c-c9fea810b245.filesusr.com/ugd/67d96c_b5d84af28c7e4db7baa5be1eb84b0c53.pdf?index=true
    • https://uploads.strikinglycdn.com/files/74893f56-0e45-4858-b505-0de03185123f/vowezawimolo.pdf
    • https://8c77b9b7-c39b-43d6-9406-6086bd2c0f93.filesusr.com/ugd/ee6770_097d7763e95f445ca0350c1d900a8a5c.pdf?index=true
    • https://s3.amazonaws.com/bivanud/sebizapojodugenajilidogi.pdf
    • https://uploads.strikinglycdn.com/files/8ff76b04-6f0a-4287-906b-2d05839762c4/zivopizuwikadin.pdf
    • https://s3.amazonaws.com/bejikefowu/bihar_board_compartmental_admit_card.pdf
    • https://s3.amazonaws.com/napoledunadigo/86534809308.pdf
    • https://uploads.strikinglycdn.com/files/a1ec837d-fcbf-4bd4-b668-468cafff3f2f/que_es_la_educacin_especial.pdf
    • https://uploads.strikinglycdn.com/files/da20936c-0c6a-4318-997f-dc70c92a8545/what_is_a_swinging_chair_called.pdf
    • https://uploads.strikinglycdn.com/files/539732ba-2107-4b71-8dee-00c9a26725e6/il-1120-st-v_instructions_2019.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000e7a4.bin
7b08d46c68b60853b766a882d64c8149e8b2b6bd8bd64194e8958ce87a8c34c7
pdf-font-stream PDF embedded font (sfnt) at offset 0xE7A4 5100 bytes
font_01_sfnt_off0000f917.bin
7cac9bbacd03e1fb6669d5d5178f1859e945de6a94096fee5b788ad89fa42302
pdf-font-stream PDF embedded font (sfnt) at offset 0xF917 10576 bytes