Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd7562ac0b7a4c58…

MALICIOUS

PDF

35.6 KB Created: 2020-08-20 21:41:36 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 23170b54b63715e835d7947e923c9aaf SHA-1: 9c2c9f64cc106d08c31ef333ae4f97ccd6693fdd SHA-256: cd7562ac0b7a4c587c36cda64f0b44123dafcc918dc7f66446fc24bdc94e2090
154 Risk Score

Malware Insights

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

The PDF contains a link to a redirector disguised as an answer key for an algebra worksheet. The PDF_MALICIOUS_REDIRECTOR_LINK heuristic and the embedded URL in the document body strongly suggest this is a phishing or redirection attempt. The ML_NYX_PDF_MALICIOUS score further supports the malicious nature of the file. No scripts were extracted, limiting the analysis of specific execution behaviors.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • 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.
  • 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/pify?keyword=evaluating+expressions+worksheet+algebra+2+answers
    • http://xemazu.envivantblog.com/uploads/1/3/0/9/130969431/fifejusim.pdf
    • http://files.stpetersnsdunboyne.com/uploads/1/3/1/1/131164479/zovesasegorejumajeke.pdf
    • https://cdn.shopify.com/s/files/1/0437/7654/0834/files/52700611737.pdf
    • https://cdn.shopify.com/s/files/1/0428/8629/9815/files/chemistry_matters_2nd_edition_textbook_answers_free_download.pdf
    • https://cdn.shopify.com/s/files/1/0461/6306/7032/files/bavobuganoroxa.pdf
    • https://cdn.shopify.com/s/files/1/0448/9897/5899/files/list_of_journal_abbreviations.pdf
    • https://cdn.shopify.com/s/files/1/0433/8145/7061/files/37782254678.pdf
    • https://cdn.shopify.com/s/files/1/0433/0248/6180/files/81300404150.pdf
    • https://cdn.shopify.com/s/files/1/0435/2393/2311/files/burnham_boiler_manual.pdf
    • https://cdn.shopify.com/s/files/1/0434/2602/1527/files/nowaratuzojumopaxogavul.pdf
    • https://cdn.shopify.com/s/files/1/0434/4463/3756/files/php_port_scanner.pdf
    • https://cdn.shopify.com/s/files/1/0430/7176/6681/files/23320888685.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00004da2.bin
3cdcab1e8581759da10f6b8c3e2c91f5231de1b6d3e89507ef33766682da6a18
pdf-font-stream PDF embedded font (sfnt) at offset 0x4DA2 5592 bytes
font_01_sfnt_off000060be.bin
d47c2d61aaab31b3d6a25b48ef218b0d5e07411f76bd83b385a5dcf50ae74a17
pdf-font-stream PDF embedded font (sfnt) at offset 0x60BE 9552 bytes