Malicious PDF — malware analysis report

Static analysis result for SHA-256 39d8ef1de3f3dd71…

MALICIOUS

PDF

41.4 KB Created: 2020-08-19 02:19:51 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: e546036c033c1df51421c3a15495d6e5 SHA-1: f35e48a4a8024d758fe2cbb6cce4102611953d15 SHA-256: 39d8ef1de3f3dd71c1fa9aeaa2e764a258be457d2d204edb1299a8b03d74347c
154 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a link farm designed to appear as a programming tutorial, but it redirects to a known malicious infrastructure. The ML classifier strongly indicated maliciousness. The primary attack vector is likely a phishing attempt leveraging a seemingly educational document to redirect users to harmful content.

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.ru/pify?keyword=8086+assembly+language+programming+tutorial+pdf
    • http://files.icollectablesonline.com/uploads/1/3/1/0/131071157/7001346.pdf
    • http://xefulugog.emilyjaneart.co.uk/uploads/1/3/0/8/130814328/4524714.pdf
    • http://demeweke.profi-solar.com/uploads/1/3/0/7/130775350/d5b5750.pdf
    • http://mudulin.renoirpropertygroup.com/uploads/1/3/1/4/131437423/856992.pdf
    • http://mogulob.weatherstonechestersprings.com/uploads/1/3/0/8/130873738/guriwofekipuw.pdf
    • https://cdn.shopify.com/s/files/1/0428/5743/1199/files/58976021237.pdf
    • https://cdn.shopify.com/s/files/1/0430/8962/5241/files/76863151018.pdf
    • https://cdn.shopify.com/s/files/1/0434/7772/9430/files/befinejufukiponepamomavus.pdf
    • https://cdn.shopify.com/s/files/1/0428/9714/6019/files/simple_compound_interest_examples_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0437/5900/9943/files/16629611803.pdf
    • https://cdn.shopify.com/s/files/1/0437/4082/3701/files/fasedidizapisudulowase.pdf
    • https://cdn.shopify.com/s/files/1/0431/7108/6485/files/xaminakawonoxadeder.pdf
    • https://cdn.shopify.com/s/files/1/0429/8699/5863/files/nuxilegagipidobepizojux.pdf
    • https://cdn.shopify.com/s/files/1/0431/2052/5476/files/56359886817.pdf
    • https://cdn.shopify.com/s/files/1/0428/0870/5187/files/19550283485.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_off0000621f.bin
11ef9bacb00270b9a8be18ec28bb3e107b6c901d5c42ec92114d69c3378aa4c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x621F 5996 bytes
font_01_sfnt_off0000765f.bin
605d1025b36f3c51aa48f8133b83379f6a1ab56a5e0a3c0e76ed1bcd78a75436
pdf-font-stream PDF embedded font (sfnt) at offset 0x765F 10080 bytes