Malicious PDF — malware analysis report

Static analysis result for SHA-256 a4b4675f02a7a0d1…

MALICIOUS

PDF

42.7 KB Created: 2020-08-09 11:23:39 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: d72bbff0b86e16275717986d731dd5cb SHA-1: 790ef0538bc0dc308470b20e167e41130dd29cc2 SHA-256: a4b4675f02a7a0d17b1ad51329d4af9ce1144f615d831bfa7e9828d5bcc05610
154 Risk Score

Malware Insights

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

The PDF was flagged as malicious due to a critical heuristic identifying it as a redirector link to known malicious infrastructure. It also contains a large number of external links, characteristic of a link farm. The embedded URL points to a redirector service, which likely leads to a phishing page or malware download. The document body contains garbled text but includes the same suspicious 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=keith+johnson+acoustic+and+auditory+phonetics+pdf
    • http://files.cozycatsanddogs.com/uploads/1/3/1/4/131406662/17b591e95d.pdf
    • http://files.anmhomedecorandmore.com/uploads/1/3/2/8/132814906/geralawevixopud.pdf
    • http://files.barbariancrossfit.com/uploads/1/3/1/4/131437736/dunero.pdf
    • https://cdn.shopify.com/s/files/1/0434/4456/8216/files/project_business_case_example.pdf
    • https://cdn.shopify.com/s/files/1/0428/9075/6252/files/71060489809.pdf
    • https://cdn.shopify.com/s/files/1/0429/8113/0394/files/65630402347.pdf
    • https://cdn.shopify.com/s/files/1/0434/3591/7464/files/8334952932.pdf
    • https://cdn.shopify.com/s/files/1/0435/4641/1162/files/3507897391.pdf
    • https://cdn.shopify.com/s/files/1/0434/1222/6206/files/romeo_juliet.pdf
    • https://cdn.shopify.com/s/files/1/0428/2309/0343/files/moxewe.pdf
    • https://cdn.shopify.com/s/files/1/0428/0372/4455/files/nufadisulani.pdf
    • https://cdn.shopify.com/s/files/1/0433/1264/4251/files/95032768264.pdf
    • https://cdn.shopify.com/s/files/1/0430/3106/8825/files/ruzasumevuvukejadati.pdf
    • https://cdn.shopify.com/s/files/1/0432/7938/4744/files/limigopotatofirebik.pdf
    • https://cdn.shopify.com/s/files/1/0433/0687/7080/files/64831632673.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_off00006839.bin
d4217b3e0c8de85498f58b9c66a91261b2ac5e121570e5ae15de1af395e7f1fe
pdf-font-stream PDF embedded font (sfnt) at offset 0x6839 5360 bytes
font_01_sfnt_off00007a81.bin
03dd9f19c5a93dfaed0a9e9bc10766439c9918d3c369ae46386e467983f50c8f
pdf-font-stream PDF embedded font (sfnt) at offset 0x7A81 10264 bytes