Malicious PDF — malware analysis report

Static analysis result for SHA-256 8fc721f80c81c97f…

MALICIOUS

PDF

40.7 KB Created: 2020-08-06 02:21:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d1c669c2b660530995cf529ccd8fba83 SHA-1: c3d30f17e78f1bdd56fa16599f14d4129acb5282 SHA-256: 8fc721f80c81c97fc6490ce2fe7b36bb1dbf958f8a7021d03a472590d4232355
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with a critical heuristic identifying a link to a known malicious redirector at `https://ttraff.ru/pify?keyword=asleep+in+the+valley+poem+pdf`. The document also functions as a link farm, directing users to a large number of other PDF files hosted on various domains, likely as part of an SEO poisoning or traffic generation scheme. The ML classifier strongly supports the malicious nature of this PDF.

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=asleep+in+the+valley+poem+pdf
    • http://files.fencestile.com/uploads/1/3/2/6/132682994/savediwodavep.pdf
    • http://fetinine.bigdogrottweilers.com/uploads/1/3/0/7/130739415/62bc624d274b.pdf
    • http://files.ericatremblayresumespecialist.com/uploads/1/3/0/8/130874543/zanepofekelo.pdf
    • http://files.triathletewithin.com/uploads/1/3/0/9/130969184/7147590.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/50833930904.pdf
    • https://cdn.shopify.com/s/files/1/0429/5763/5743/files/32103638950.pdf
    • https://cdn.shopify.com/s/files/1/0431/4746/0768/files/11989209681.pdf
    • https://cdn.shopify.com/s/files/1/0440/9245/7112/files/brahmaputra_river_system.pdf
    • https://cdn.shopify.com/s/files/1/0428/5494/0828/files/mavobogapebevemamenisot.pdf
    • https://cdn.shopify.com/s/files/1/0435/8730/5629/files/rupesovikanevu.pdf
    • https://cdn.shopify.com/s/files/1/0427/4647/8758/files/suffix_ness_exercises.pdf
    • https://cdn.shopify.com/s/files/1/0435/2756/9576/files/56553305325.pdf
    • https://cdn.shopify.com/s/files/1/0430/9044/4445/files/9516760689.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/rikakaxudote.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_off00006258.bin
adf0a30e58ed9a034cce5873b529d4acf82b107a6a0719437a71e0e0f615b7b9
pdf-font-stream PDF embedded font (sfnt) at offset 0x6258 5336 bytes
font_01_sfnt_off0000746b.bin
8f71324db5c2260dc78c85cb726bfb4d45e9860bab68e5cdf54ee75e29da86d0
pdf-font-stream PDF embedded font (sfnt) at offset 0x746B 9876 bytes