Malicious PDF — malware analysis report

Static analysis result for SHA-256 031a9ecc09ac6393…

MALICIOUS

PDF

32.7 KB Created: 2020-08-24 00:16:03 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 8ba44f8e7832c1eebece3a5f65b6d740 SHA-1: 21408339a6a553acd9ef0afe409f5460454dd401 SHA-256: 031a9ecc09ac6393c113f2c7eb6af569d98d705983fd95138555ebf405aa2de4
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

The PDF document contains a lure related to a 'chemistry olympiad 2018 answer key' and embeds numerous links. One of these links, https://ttraff.com/pify?keyword=chemistry+olympiad+2018+answer+key, is identified as a malicious redirector. The document also exhibits characteristics of a link farm, with many embedded URLs pointing to PDF files hosted on various domains, suggesting an attempt to manipulate search engine results or distribute further malicious content. The ML classifier strongly flagged this PDF as malicious.

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=chemistry+olympiad+2018+answer+key
    • http://vugokakep.mtchoirs.com/uploads/1/3/1/4/131408280/4158123.pdf
    • http://files.azcornholeassociation.com/uploads/1/3/0/7/130775063/xogesexasezaxesoj.pdf
    • http://xadagogar.helentclark.org/uploads/1/3/0/7/130738615/jamora.pdf
    • http://files.duranet.ca/uploads/1/3/2/8/132815054/1919046.pdf
    • http://www.ascendercorp.com/
    • http://www.ascendercorp.com/typedesigners.html
    • https://cdn.shopify.com/s/files/1/0435/5204/7255/files/53649177290.pdf
    • https://cdn.shopify.com/s/files/1/0434/3899/7669/files/welixuwireto.pdf
    • https://cdn.shopify.com/s/files/1/0447/2481/3977/files/adblock_plus_firefox.pdf
    • https://cdn.shopify.com/s/files/1/0434/1320/9246/files/binavuxugezurezoro.pdf
    • https://cdn.shopify.com/s/files/1/0430/9378/6791/files/wezikijinajuzepar.pdf
    • https://cdn.shopify.com/s/files/1/0428/5480/9759/files/kotisutezigo.pdf
    • https://cdn.shopify.com/s/files/1/0437/9276/0994/files/28877151859.pdf
    • https://cdn.shopify.com/s/files/1/0429/7592/0282/files/nufevuvurovosanos.pdf
    • https://cdn.shopify.com/s/files/1/0433/3545/0774/files/anatomy_physiology_and_pathology_by_body_systems.pdf
    • https://cdn.shopify.com/s/files/1/0429/8987/9445/files/xenoworivevonawape.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/
    • http://scripts.sil.org/OFL

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off000041eb.bin
c32553234c4702f95947fab0f745f13a013bce1b82014a5c7029f3014eb4beb9
pdf-font-stream PDF embedded font (sfnt) at offset 0x41EB 5884 bytes
font_01_sfnt_off000055e2.bin
7be4d4ea49d012ad16651d5bb082b0c458405b9e7dce82f7bcef2e64dd9bc33f
pdf-font-stream PDF embedded font (sfnt) at offset 0x55E2 9464 bytes