Malicious PDF — malware analysis report

Static analysis result for SHA-256 caa8129db00b5f95…

MALICIOUS

PDF

40.8 KB Created: 2020-08-09 12:59:29 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 09f756622687958b3ebf73272553b28c SHA-1: 672174632c6635f0fba49de221f1b53353d5bca9 SHA-256: caa8129db00b5f956e08adf7212a4c2ab4161145b58104746773c74e67113d98
152 Risk Score

Malware Insights

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

The PDF contains numerous embedded links, with one identified as a known malicious redirector. The document body, though partially corrupted, contains text related to 'free pdf' downloads, suggesting a lure. The heuristic firings confirm the presence of malicious redirector links and a link farm, indicating an attempt to drive traffic to potentially harmful sites. 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=artificial+intelligence+with+python+prateek+joshi+free+pdf
    • http://jopasurig.mythnmagik.com/uploads/1/3/1/3/131380480/nelusupupozego-jakemudovulikur-fuzolilinodosa.pdf
    • http://files.higherorderinnovation.com/uploads/1/3/2/6/132681713/8784782.pdf
    • http://files.rcarteephotos.com/uploads/1/3/0/7/130776573/5da2937332.pdf
    • http://dadurim.eycdioatl.org/uploads/1/3/2/8/132814930/3360116.pdf
    • https://cdn.shopify.com/s/files/1/0432/8144/9126/files/58250800819.pdf
    • https://cdn.shopify.com/s/files/1/0432/7496/1059/files/bu_admission_circular_2020_20.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/38935964995.pdf
    • https://cdn.shopify.com/s/files/1/0429/5763/5735/files/57580954433.pdf
    • https://cdn.shopify.com/s/files/1/0432/8367/7339/files/25612366354.pdf
    • https://cdn.shopify.com/s/files/1/0428/5333/5207/files/nivawogat.pdf
    • https://cdn.shopify.com/s/files/1/0434/2385/8850/files/timber_mod_1._7._10.pdf
    • https://cdn.shopify.com/s/files/1/0430/7252/0352/files/55489139497.pdf
    • https://cdn.shopify.com/s/files/1/0431/3110/9540/files/30095744269.pdf
    • https://cdn.shopify.com/s/files/1/0433/6291/0376/files/pewawitotilojopuguxuku.pdf
    • https://cdn.shopify.com/s/files/1/0441/3915/1512/files/77818350333.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_off00005f34.bin
fbf751ae317b6428111280f52f3d102c3ce03d716d632d8a2e7a6519634625c7
pdf-font-stream PDF embedded font (sfnt) at offset 0x5F34 5740 bytes
font_01_sfnt_off000072d5.bin
b63c30804db77880f14d696f8f7a1fdb58e7483243018efe7567fb885d2c56e8
pdf-font-stream PDF embedded font (sfnt) at offset 0x72D5 10212 bytes