Malicious PDF — malware analysis report

Static analysis result for SHA-256 8cd021e3a69a7b82…

MALICIOUS

PDF

48.5 KB Created: 2020-09-09 16:01:55 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2f35be96a819f348b53cb868b5f36bb2 SHA-1: 423ecc772daf4a26be4aa30aec24323117907c9d SHA-256: 8cd021e3a69a7b82a86dd761f8496978544fbab2effd12710edd24fec4dc4cb2
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.001 User Execution: Malicious Link T1059.001 Command and Scripting Interpreter: PowerShell

The PDF contains a mass of external links, many of which point to a redirector infrastructure. The primary malicious link identified is https://ttraff.me/wix?keyword=mcgraw+hill+accounting+textbook+pdf, which is likely used to distribute further malware or phishing content. The ML classifier strongly indicated maliciousness, and the presence of numerous SEO-optimized PDF links suggests a link farm or spamming operation.

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.me/wix?keyword=mcgraw+hill+accounting+textbook+pdf
    • http://lekewamo.mntcapa.org/uploads/1/3/0/8/130873843/roganuru_vivataboxi.pdf
    • http://files.flowersfromsarahsgarden.com/uploads/1/3/2/6/132681576/bopivonunufikem-lojabuvama.pdf
    • http://files.alexandrudina.com/uploads/1/3/0/7/130740124/donirugor-zukosilenav.pdf
    • http://wubiv.alexandriatalley.com/uploads/1/3/0/7/130775565/tejexexetanonot_lomudi_lobokojoxo_vatexiwes.pdf
    • http://files.shinjudojo.com/uploads/1/3/0/7/130776589/lolabajadubetibusus.pdf
    • https://static.usrfiles.com/ugd/e3834b_e364bf61f0ed47d582e2591453d62cd0.pdf
    • https://static.usrfiles.com/ugd/1e533a_e87e1633a050477185cd2b3cee6b4fe6.pdf
    • https://static.usrfiles.com/ugd/b47706_f047b9fc13b74560b33c9823f0c20be0.pdf
    • https://cdn.shopify.com/s/files/1/0436/4982/6969/files/examples_of_deductive_and_inductive_reasoning.pdf
    • https://cdn.shopify.com/s/files/1/0431/3245/3015/files/6615580725.pdf
    • https://cdn.shopify.com/s/files/1/0433/5481/6665/files/57948327649.pdf
    • https://cdn.shopify.com/s/files/1/0461/9422/9406/files/fatufidu.pdf
    • https://cdn.shopify.com/s/files/1/0432/4386/4228/files/pobez.pdf
    • https://cdn.shopify.com/s/files/1/0433/5845/3918/files/sodium_hydroxide_liquid_msds_sheet.pdf
    • https://cdn.shopify.com/s/files/1/0440/0414/7350/files/33941086170.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_off0000787e.bin
96730433886ef14c2ce1f81b4d64f703725bd758c9556a94f4c4362850c26971
pdf-font-stream PDF embedded font (sfnt) at offset 0x787E 5608 bytes
font_01_sfnt_off00008bb5.bin
1385b02536d6485ebdae2ab1f17e5a200e4fe19a0633c1ac1ce4943449be4e30
pdf-font-stream PDF embedded font (sfnt) at offset 0x8BB5 12564 bytes