Malicious PDF — malware analysis report

Static analysis result for SHA-256 82d112342678aa1e…

MALICIOUS

PDF

47.0 KB Created: 2020-08-12 08:37:04 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 33447a3d8921371db3a3e33a4836dbb0 SHA-1: 67cdcaf2eb249b15db455d007427063a53909937 SHA-256: 82d112342678aa1e418ddc6776342fd6c648bc07ca49b4efbb8bc9f23c224859
152 Risk Score

Malware Insights

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

The PDF contains a large number of embedded links, with one specifically identified as a malicious redirector. The heuristic 'PDF_SEO_LINK_FARM' indicates a mass of external PDF links, suggesting an attempt to manipulate search engine results or distribute content through a link farm. The ML classifier also strongly indicated maliciousness. The primary malicious IOC is the redirector URL.

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=caulerpa+sertularioides+pdf
    • http://files.deirdreedsign.com/uploads/1/3/0/7/130739315/3356270.pdf
    • http://files.teachertechtraining.org/uploads/1/3/1/4/131406344/63f25f2.pdf
    • http://files.onelightinstitute.org/uploads/1/3/2/8/132814241/283b245e4f.pdf
    • https://cdn.shopify.com/s/files/1/0430/1075/2663/files/98490773751.pdf
    • https://cdn.shopify.com/s/files/1/0431/3815/4653/files/59064849529.pdf
    • https://cdn.shopify.com/s/files/1/0438/2218/6656/files/meredifefemujuvuxoku.pdf
    • https://cdn.shopify.com/s/files/1/0430/5528/4378/files/xemubipitunerudepubezige.pdf
    • https://cdn.shopify.com/s/files/1/0431/5371/9453/files/carb_cycling_meal_plan_for_fat_loss.pdf
    • https://cdn.shopify.com/s/files/1/0432/3593/4370/files/nogorosuwakefokawifomar.pdf
    • https://cdn.shopify.com/s/files/1/0440/8170/9206/files/jubepikozugobaselam.pdf
    • https://cdn.shopify.com/s/files/1/0439/1036/5339/files/insulin_aspart_davis_drug_guide.pdf
    • https://cdn.shopify.com/s/files/1/0429/9328/7321/files/86971116318.pdf
    • https://cdn.shopify.com/s/files/1/0430/9018/2304/files/zonuforanotevagajibisatef.pdf
    • https://cdn.shopify.com/s/files/1/0438/0744/1053/files/knee_arthroscopy_portals.pdf
    • https://cdn.shopify.com/s/files/1/0427/9028/9574/files/56651379595.pdf
    • https://cdn.shopify.com/s/files/1/0431/5735/6695/files/antibiotics_review.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_off00007c49.bin
c35d4b105c4476fbcb817488fb36aa11bf0ad95917ec30887a7326b3e88b01ec
pdf-font-stream PDF embedded font (sfnt) at offset 0x7C49 4940 bytes
font_01_sfnt_off00008d1f.bin
af913fb6ed9581beff009dca3a606fb9614626a7584cfc6d3642d98e1e6a6ce0
pdf-font-stream PDF embedded font (sfnt) at offset 0x8D1F 9980 bytes