Malicious PDF — malware analysis report

Static analysis result for SHA-256 b1caa778bb3e8f5f…

MALICIOUS

PDF

34.9 KB Created: 2020-08-09 18:19:10 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 2d689ccdd9aa6f4369512fc5d6754176 SHA-1: 81e6172779856d02d7c8cba11d53a9209420c8eb SHA-256: b1caa778bb3e8f5f82c48d20dd2779195cfdd10fe90b635fa25dc286602f7c97
152 Risk Score

Malware Insights

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

The PDF contains multiple embedded links, with one critical heuristic firing indicating a link to known malicious redirector infrastructure. The document body and embedded links suggest a lure for free PDF downloads, specifically 'Pathophysiology 7th edition pdf free'. The primary malicious URL identified is https://ttraff.com/pify?keyword=pathophysiology+7th+edition+pdf+free, which is likely used to redirect users to further malicious content. The ML classifier also strongly indicated maliciousness.

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.com/pify?keyword=pathophysiology+7th+edition+pdf+free
    • http://files.ourchildrenshomestead.org/uploads/1/3/1/3/131379397/8313f4f.pdf
    • http://files.anndcroghanart.com/uploads/1/3/0/7/130776578/turidufuletax.pdf
    • http://files.carolynlaine.com/uploads/1/3/1/3/131398008/fbb86b0a56f.pdf
    • http://files.chennaishiayouth.com/uploads/1/3/0/7/130740589/joxax.pdf
    • https://cdn.shopify.com/s/files/1/0428/7676/4327/files/jarezabimikubipepovenuta.pdf
    • https://cdn.shopify.com/s/files/1/0437/4616/4897/files/finowe.pdf
    • https://cdn.shopify.com/s/files/1/0432/6175/5547/files/medieval_town_minecraft.pdf
    • https://cdn.shopify.com/s/files/1/0427/4031/8375/files/60384023974.pdf
    • https://cdn.shopify.com/s/files/1/0432/3885/0728/files/fokuvukebufikuxama.pdf
    • https://cdn.shopify.com/s/files/1/0433/2565/3160/files/hughes_hallett_calculus_5th_edition.pdf
    • https://cdn.shopify.com/s/files/1/0430/6547/5229/files/wutadato.pdf
    • https://cdn.shopify.com/s/files/1/0428/6719/6063/files/kuludox.pdf
    • https://cdn.shopify.com/s/files/1/0430/7851/6885/files/45029085659.pdf
    • https://cdn.shopify.com/s/files/1/0434/0740/9310/files/14283833080.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_off00004b12.bin
356a877537c4328513ed13760cd6055641218542fed9606575d4a2eb49192ab9
pdf-font-stream PDF embedded font (sfnt) at offset 0x4B12 5484 bytes
font_01_sfnt_off00005dc9.bin
ac5632a0630fe27c47dc013e77b780bd0914ec08e02cbd917712e12f786cacac
pdf-font-stream PDF embedded font (sfnt) at offset 0x5DC9 9744 bytes