Malicious PDF — malware analysis report

Static analysis result for SHA-256 ac19bd3af15333b2…

MALICIOUS

PDF

43.0 KB Created: 2020-07-18 05:37:54 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2020-09-07
MD5: 9fbb793cb5844e77f7c6b7a0bca5f048 SHA-1: 05698933ceadd28fbe69ebf96192b4f66f960f6e SHA-256: ac19bd3af15333b2f10b9da5bd4896fbe4fa1b08f84e1f8471b15aff6a415323
194 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF file contains numerous embedded links, with one specifically pointing to a known malicious redirector. The document body, though heavily obfuscated, contains text related to 'Sudoku puzzles pdf hard', suggesting a lure. The heuristic 'PDF_MALICIOUS_REDIRECTOR_LINK' confirms the presence of a link to malicious infrastructure, and 'PDF_SEO_LINK_FARM' indicates a large number of external links, likely for SEO manipulation or to host further malicious content.

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.cc/wb?keyword=sudoku%20puzzles%20pdf%20hard In PDF document text
    • http://files.versaillesfourthofjuly.com/uploads/1/3/1/4/131437158/4302449.pdfIn PDF document text
    • http://files.birgfish.com/uploads/1/3/2/8/132815054/bovomaxibuxu.pdfIn PDF document text
    • http://files.charitycora.org/uploads/1/3/1/4/131407980/xigitibarawasad.pdfIn PDF document text
    • http://files.widisposal.com/uploads/1/3/1/4/131438642/kefunolonizowituf.pdfIn PDF document text
    • http://files.lorettacrogersnovels.com/uploads/1/3/1/1/131163833/sarijezerevabe_riwujege_nupetis.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/1/0436/4071/7462/files/49227050784.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/6044/5855/files/34023555858.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0434/5780/6488/files/9698040007.pdfIn PDF document text
    • https://jubujotilo.files.wordpress.com/2020/06/52773005894.pdfIn PDF document text
    • https://demovajes.files.wordpress.com/2020/07/13362086586.pdfIn PDF document text
    • https://lotopakaxil.files.wordpress.com/2020/07/suxorudomok.pdfIn PDF document text
    • https://dabenuroz.files.wordpress.com/2020/07/32421567820.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/99913566500.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/5031/1579/files/38335398406.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/9622/0572/files/jelupojiganun.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8451/3429/files/1917214422.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0431/5122/9089/files/govoloxodis.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0433/8620/8406/files/82078035320.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8759/3632/files/9883259672.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0430/8077/7882/files/22856893718.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0427/5827/5238/files/48894378721.pdfIn PDF document text
    • https://cdn.shopify.com/s/files/1/0428/9154/2681/files/4988047420.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_off00006b37.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x6B37 4996 bytes
SHA-256: 443bf5a755d631eafdfb7f593d8d355c320e24c2142de79c78802d6c763e1bcf
font_01_sfnt_off00007c4e.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x7C4E 10052 bytes
SHA-256: 47ccdf29a21f070476f16cc4d6677cfa2d02cb7929eb10e5f27a6c9d13088ea7