Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1b8c0d9138542d3…

MALICIOUS

PDF

42.0 KB Created: 2020-08-18 20:27:23 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 3344e984cc20e5874a6c7ccc1683e87c SHA-1: 85632525e4c63d3633dee1196946f866b8557190 SHA-256: b1b8c0d9138542d358b8d2fe85551c04d3c0c1d4a36429a44ce49151eb9608fb
152 Risk Score

Malware Insights

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

The PDF document contains a large number of embedded links, a technique often used to create link farms for SEO manipulation or to redirect users to malicious sites. One critical heuristic identified a link to known malicious redirector infrastructure at 'https://ttraff.ru/pify?keyword=sololearn+2.+5.+5+mod+apk'. The ML classifier also strongly indicated maliciousness. No scripts were extracted, but the document body and heuristics point to a link-based redirection attack.

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=sololearn+2.+5.+5+mod+apk
    • http://files.birdsinblooom.com/uploads/1/3/1/3/131380292/4073625.pdf
    • http://files.floridaballetconservatory.com/uploads/1/3/0/7/130776245/taduvunawawopedonuv.pdf
    • http://files.radmtfitness.com/uploads/1/3/1/1/131164479/lajixexofutat-pinudefosis.pdf
    • https://cdn.shopify.com/s/files/1/0428/4976/3487/files/27643395185.pdf
    • https://cdn.shopify.com/s/files/1/0431/7259/3832/files/rajuwij.pdf
    • https://cdn.shopify.com/s/files/1/0432/3305/0779/files/zibivovikuze.pdf
    • https://cdn.shopify.com/s/files/1/0427/4028/5607/files/kekebopifexobazo.pdf
    • https://cdn.shopify.com/s/files/1/0431/1393/9110/files/ca_dmv_practice_test_2016.pdf
    • https://cdn.shopify.com/s/files/1/0437/8191/4781/files/algebra_2_practice_test_with_answers.pdf
    • https://cdn.shopify.com/s/files/1/0428/9314/8313/files/rirumalivejafutebiw.pdf
    • https://cdn.shopify.com/s/files/1/0434/7189/6741/files/catia_v5r21_book.pdf
    • https://cdn.shopify.com/s/files/1/0430/6858/8194/files/renaissance_art.pdf
    • https://cdn.shopify.com/s/files/1/0440/1663/1973/files/4142401616.pdf
    • https://cdn.shopify.com/s/files/1/0433/9610/4341/files/wokaditazorulirabesewe.pdf
    • https://cdn.shopify.com/s/files/1/0446/7025/5267/files/micro_center_seattle.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_off0000658a.bin
32c2c1ac9677ebd98d497f65a45e02158412ae9f00b4fcccc5653ab48c6fa8c1
pdf-font-stream PDF embedded font (sfnt) at offset 0x658A 5384 bytes
font_01_sfnt_off000077c0.bin
7b63cc71f24b05a1289f83e007a0ddf28390c8dfdb0dc45824b566181843c2c4
pdf-font-stream PDF embedded font (sfnt) at offset 0x77C0 10292 bytes