Malicious PDF — malware analysis report

Static analysis result for SHA-256 85626b9f7e6f0c84…

MALICIOUS

PDF

41.9 KB Created: 2020-07-18 08:44:46 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-24
MD5: ad629c8d699a1b3fa3dc9111fd736f76 SHA-1: c5e1c1069418562df10a35da9cb219888983d493 SHA-256: 85626b9f7e6f0c84fe1e8a98c1745e23e2876a21cb4e31bba428571db8d1a7a7
194 Risk Score

Malware Insights

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

The PDF contains multiple heuristics indicating malicious redirector links and a link farm, pointing to the URL https://ttraff.com/wb?keyword=articles%20grammar%20worksheet. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the embedded URLs and link farm structure suggest an attempt to direct users to malicious infrastructure, likely for phishing or malware delivery.

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://ttraff.com/wb?keyword=articles%20grammar%20worksheet In PDF document text
    • http://files.cnycommunityacu.com/uploads/1/3/1/4/131453982/5284345.pdfIn PDF document text
    • http://files.acadianaplumbersassociation.com/uploads/1/3/1/3/131381721/nifumodikamunib-xuzevedaxelogon.pdfIn PDF document text
    • http://files.aggielions.org/uploads/1/3/1/1/131164387/kosoka.pdfIn PDF document text
    • http://files.evadowdinternational.com/uploads/1/3/2/6/132681665/564467ae.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://xanosaxa.files.wordpress.com/2020/07/migajiwilopupizut.pdfIn PDF document text
    • https://nubudin.files.wordpress.com/2020/06/webol.pdfIn PDF document text
    • https://xoxapuziri.files.wordpress.com/2020/06/76219333994.pdfIn PDF document text
    • https://nodezebibun.files.wordpress.com/2020/06/45321680690.pdfIn PDF document text
    • https://pamowuvesez.files.wordpress.com/2020/06/72248271809.pdfIn PDF document text
    • https://kogezes.files.wordpress.com/2020/07/nodisugonakefejaxepa.pdfIn PDF document text
    • https://zapuwujila.files.wordpress.com/2020/07/kedotakagobovovitusalubom.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/8606/2495/files/97741316284.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/6838/3642/files/70897917576.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/1019/5605/files/maseri.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/1506/1153/files/vovogiwosuvamazapejub.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/8478/3509/files/88638696024.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/3884/9694/files/radada.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/3350/9534/files/basubaninaf.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 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000663b.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x663B 5040 bytes
SHA-256: 4a898421488d4db292bfd054222f3cfda6ae75ccf79748e56690021c0fc755b1
font_01_sfnt_off00007766.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7766 10252 bytes
SHA-256: 8e17baaa072b7b96f66199b4540aaaca8b0d286e6d7ee7bfdb7a9f4911e341b6