Malicious PDF — malware analysis report

Static analysis result for SHA-256 20631dc5fa58b4e2…

MALICIOUS

PDF

54.5 KB Created: 2020-07-19 03:42:17 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-04
MD5: ce4f6a3211e86b19ea3c736edc5358ea SHA-1: 226a796832b543f4d82acdfe18afdfcc02219921 SHA-256: 20631dc5fa58b4e2d014e861044b40af9bb403bd078ec25bf8a86677a0d486b9
194 Risk Score

Malware Insights

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

The PDF contains embedded links to a redirector URL, identified as malicious and used in an SEO link farm tactic. The document body text, though heavily obfuscated, suggests a lure related to 'Ged prep test pdf'. The ML classifier strongly indicates maliciousness, and the overall structure points to a phishing or scam attempt leveraging SEO manipulation.

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.ru/wb?keyword=ged%20prep%20test%20pdf In PDF document text
    • http://files.sherieunfiltered.com/uploads/1/3/2/8/132815961/a59b4b501cc8.pdfIn PDF document text
    • http://files.arlordpac.ca/uploads/1/3/1/3/131383426/buzip_fitewewasalawes_dufufekelul_sekigibulumazi.pdfIn PDF document text
    • http://files.zachpiercemusic.com/uploads/1/3/1/0/131070651/547ba.pdfIn PDF document text
    • http://files.livingatthedistillery.com/uploads/1/3/0/7/130776591/dilunokewanubol-duvafopap-pijikofusejoji.pdfIn PDF document text
    • http://files.northmetroweekday.com/uploads/1/3/1/8/131856954/bububawujitigudevup.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/84113106953.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/medade.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/0360/8216/files/20344658637.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/65294746239.pdfIn PDF document text
    • https://sojukitibo.files.wordpress.com/2020/06/56035642429.pdfIn PDF document text
    • https://wabuvodulix.files.wordpress.com/2020/07/61363676175.pdfIn PDF document text
    • https://pevoruzon.files.wordpress.com/2020/06/buwusugexasisa.pdfIn PDF document text
    • https://kemubebi.files.wordpress.com/2020/07/mapuzagageduwalis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0432/3393/5515/files/zitepevajuxumedirovu.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/71061356311.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/1983/7346/files/zomisafatakomuzugadapezed.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0436/6244/2661/files/45506740684.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/5827/5238/files/84660393038.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/sozolomunegodufedawugiwe.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0437/6972/5080/files/wogubupudinafef.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0429/0864/7580/files/linuj.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/0041/4883/files/vemasu.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_off00009954.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x9954 4348 bytes
SHA-256: c43708be612e947e38cf4e39b838b39984ae8956064329183b56a9a029695125
font_01_sfnt_off0000a82f.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xA82F 10660 bytes
SHA-256: 370f6702ad8e9400397ec4dd41f7885b8552d66e22930dff3dcbfd5d4f003b70