Malicious PDF — malware analysis report

Static analysis result for SHA-256 39b4f1b381e844fb…

MALICIOUS

PDF

54.5 KB Created: 2020-09-29 20:40:33 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-05-15
MD5: 94a62646a2ff14c3ab83c2d2a995b162 SHA-1: b298374b444c6926c3536f953d042e42e1abbfb2 SHA-256: 39b4f1b381e844fb37cf8ffbe623e296cc54f09c61bbda4006354df3df701359
234 Risk Score

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 6

  • 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.
  • PDF link to algorithmically-generated URL high PDF_RANDOM_URL_LINK
    PDF contains a clickable HTTP(S) link whose host looks algorithmically generated (pronounceable-random labels) and whose path/query carries a long high-entropy token. This is the randomized-redirector pattern of malspam phishing lures — the visible document is only a prompt — not a PDF parser vulnerability.
  • Image lure linking to an SEO redirector (free-download phishing) high PDF_SEO_UTM_REDIRECTOR_LINK
    PDF embeds an image with little or no body text and a clickable link to a multi-word utm_term / FeedBurner-proxied SEO redirector — the 'free ebook / solution-manual / document download' phishing family that ranks for natural-language search queries and routes the user into a payload/redirect chain. The PDF carries no exploit; the risk is the linked destination. Flagged structurally (image lure + SEO redirector) so it does not depend on a ClamAV/ML signature, and regardless of how many filler text pages the lure carries.
  • 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://ggtraff.ru/strik?keyword=barium+swallow+technique+pdf In PDF document text
    • https://site-1036640.mozfiles.com/files/1036640/34798583146.pdfIn PDF document text
    • https://site-1037887.mozfiles.com/files/1037887/39672000281.pdfIn PDF document text
    • https://site-1037156.mozfiles.com/files/1037156/69374504309.pdfIn PDF document text
    • https://site-1037172.mozfiles.com/files/1037172/duripubudibumekaw.pdfIn PDF document text
    • http://ruxep.be-your-boss.net/uploads/1/3/1/6/131606284/b77d11572.pdfIn PDF document text
    • http://kemesofa.integritybuildersandassociates.com/uploads/1/3/0/8/130813042/togevive_baxoxenazerej.pdfIn PDF document text
    • http://files.wisconsinlitmap.com/uploads/1/3/1/3/131381464/tidelijiposovu-jidotamuzifa-wufiwufon-zinifinamibu.pdfIn PDF document text
    • http://files.paradise-wings-jamaica.com/uploads/1/3/2/3/132302749/xukij.pdfIn PDF document text
    • http://files.lilliandunham.com/uploads/1/3/2/7/132740619/mapozurafivaxurolone.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.daltonmaag.com/In PDF document text
    • https://cdn.shopify.com/s/files/1/0433/1814/9285/files/22651315931.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/4571/6129/files/intellectual_property_infringement_letter_template.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/7142/9016/files/carrom_board_game_rules_in_telugu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0461/3917/9161/files/mafit.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0438/8395/4328/files/android_13_dokkan_str.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/0316/6369/files/veduzix.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0461/1355/4596/files/feraworexozixibojivomupuj.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://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000084f2.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x84F2 5544 bytes
SHA-256: d5c532a80b666a36dd524582dd428aafd12335802187f4dda78fce52357cfde9
font_01_sfnt_off000097b0.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x97B0 12128 bytes
SHA-256: 711ebe919ba250ff135096a8168c4d21d6f15a4cec26d0cca264e1dbea3469e4
font_02_sfnt_off0000bf23.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xBF23 4324 bytes
SHA-256: 4fcfa7c68d76e23b667942a3ac892d2d5d88346478daafc61479ad4df4af3dd3