Malicious PDF — malware analysis report

Static analysis result for SHA-256 7a2657b85c8f8eb3…

MALICIOUS

PDF

39.6 KB Created: 2020-10-25 22:39:45 +02:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-09-14
MD5: 0653d9b23239352c5b95fdea5988d8b6 SHA-1: 93bac666ada518fda259600691fe5a8d06f1ccdf SHA-256: 7a2657b85c8f8eb3a614a3cd69c97426c46f3a94f217b5b6c450f14db29410a9
194 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic firing indicating it links to known malicious redirector infrastructure. The document body, though heavily obfuscated, contains a URL that matches the redirector found in the heuristics. The presence of many links to S3 buckets, some flagged as benign, suggests an attempt to blend malicious links with seemingly legitimate ones in an SEO-like fashion.

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.
  • 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://cctraff.ru/strik?keyword=k%2525C4%2525B1n%2525C4%2525B1f%2525C4%2525B1r+bedrenk+olur+nota In PDF document text
    • https://cdn-cms.f-static.net/uploads/4366366/normal_5f8b7851c8dd1.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4390069/normal_5f8ec024d5b6e.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4369313/normal_5f8a596956ba5.pdfIn PDF document text
    • https://cdn-cms.f-static.net/uploads/4365582/normal_5f87b40d2ca0b.pdfIn PDF document text
    • https://bedizegoresupa.weebly.com/uploads/1/3/1/3/131379398/8e42bfb8d1b0f.pdfIn PDF document text
    • https://zalopajozi.weebly.com/uploads/1/3/1/4/131453352/97103f78e4d.pdfIn PDF document text
    • https://xujaxivef.weebly.com/uploads/1/3/1/4/131438557/8e9af831d.pdfIn PDF document text
    • https://jewajufigojoxi.weebly.com/uploads/1/3/1/4/131438211/zewilifewel-jaruz-dilelarenuk.pdfIn PDF document text
    • https://pevinuwipe.weebly.com/uploads/1/3/0/8/130873962/xozilepiga_sexute_natuj.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://s3.amazonaws.com/naxizugenabi/benami_act_2016.pdfIn PDF document text
    • https://s3.amazonaws.com/xanebavifamopez/ribiwisawitimik.pdfIn PDF document text
    • https://s3.amazonaws.com/zetare/vobivokazajefewupukegag.pdfIn PDF document text
    • https://s3.amazonaws.com/vikukinumet/basic_concepts_of_computer_architecture.pdfIn PDF document text
    • https://s3.amazonaws.com/wizidimawag/difference_between_absolute_poverty_and_relative_poverty.pdfIn PDF document text
    • https://s3.amazonaws.com/xojafemori/wuxufunonujano.pdfIn PDF document text
    • https://s3.amazonaws.com/mijedusovineti/biochemistry_free_books.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0438/6127/8870/files/66837392248.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0497/8494/6850/files/jamewag.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0488/2310/7749/files/23387433857.pdfIn PDF document text
    • https://s3.amazonaws.com/mudurixo/26429255195.pdfIn PDF document text
    • https://s3.amazonaws.com/zevutebulaworel/ejercicios_categorias_gramaticales_2o_eso.pdfIn PDF document text
    • https://s3.amazonaws.com/nopomewegobij/74058572749.pdfIn PDF document text
    • https://s3.amazonaws.com/gowebabuxogiro/57432648839.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_off00004ed9.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x4ED9 4764 bytes
SHA-256: 19f21788f19f364e22e517c849f78849728cc9f8aa0e271e3d4cc09884720b32
font_01_sfnt_off00005f14.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x5F14 9896 bytes
SHA-256: 8a6f1b8f2fd1caf276343b5358ad502329b8b13402677e15ebdcbdda6ff7f67d
font_02_sfnt_off000080e5.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x80E5 4324 bytes
SHA-256: 1158d95dac44631f497756703988ba3645251422e7ff0015d3fca430225e7c3e