Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8cd6d760a029188…

MALICIOUS

PDF

90.2 KB Created: 2021-07-23 09:44:47 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: ea07134dbf15ee1230bfd64205dc10b9 SHA-1: db9929483290b9e6406d464700bda8c2fe54de5e SHA-256: a8cd6d760a029188137daeab9f653b8ecd6605062f3d71216afb5618011e2ff5
96 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1203 Exploitation for Client Execution

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads or disposable hosting, indicating a link farm or redirection scheme. The ML classifier strongly flagged this PDF as malicious. While no scripts were extracted, the presence of a link farm and compromised hosting suggests an attempt to direct users to malicious sites, potentially for phishing or malware distribution.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9970

Heuristics 5

  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • 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://www.reachcast.ca/wp-content/plugins/super-forms/uploads/php/files/7b26b5dfa6675f4aa6088a7b42fe036a/40551740113.pdf
    • http://dragonera.cn/admin/userfiles/file/gawaxubofobunij.pdf
    • http://ne-moloko.ee/wp-content/plugins/super-forms/uploads/php/files/4bae715067fc9eff3e5fbae67b56d03a/4944824456.pdf
    • http://hillhouseclassof1961.com/clients/c/c9/c9b049383fb65e98d0a4dcab6c176392/File/90966639084.pdf
    • http://cropscipublisher.com/files/upfiles/file/46237592934.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/160fa30db533c7---23564064286.pdf
    • https://equator-maritime.com/userfiles/file/jagiviwujagipeku.pdf
    • https://www.paseppe.gr/ckfinder/userfiles/files/78374009199.pdf
    • http://22vek-omsk.ru/fck_editor_files/files/79886311746.pdf
    • http://for-rent-leuven.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a16fe88129c---94238341399.pdf
    • http://lempreintedubois.fr/userfiles/lempreintedubois.fr/file/73024056450.pdf
    • http://emeraldoutback.com/clients/f/f6/f61299a274fa8fdb0c00f5b1ed511d42/File/gasibuzuvofodanajap.pdf
    • http://www.pirac.org/wp-content/plugins/super-forms/uploads/php/files/d5ea14a4d92555502936b1a6a01ca430/48684519656.pdf
    • https://brakos.it/file/68017203191.pdf
    • https://purebodycare.courses/wp-content/plugins/super-forms/uploads/php/files/tlgo8ou830602thnpfohlgkh4u/54640839957.pdf
    • https://www.hausbootgeiseltalsee.de/wp-content/plugins/super-forms/uploads/php/files/tjeiedv9ul6oqet31k1uk707bq/37707979086.pdf
    • https://walkandsmile.com/userfiles/file/pitofuxusekoveg.pdf
    • https://chp-travel.ir/data/file/99535020319.pdf
    • https://arizonalightingsales.com/wp-content/plugins/super-forms/uploads/php/files/9dae84235114fd5dfcb1d664c5542bb3/89577296011.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/160e02967171e0---62422439633.pdf
    • https://www.peeryhotel.com/wp-content/plugins/super-forms/uploads/php/files/ff550e78a272988ed0ac375a21362b80/25083161344.pdf
    • http://plncse.hu/php_data/file/varaloj.pdf
    • http://samnakthodrahassob.com/userfiles/file/86124510648.pdf
    • https://www.rowtheerne.com/wp-content/plugins/super-forms/uploads/php/files/d312bbf88ad73b0f191b6ba846841d0f/41859859638.pdf
    • https://jxlmedu.com/file/files/20210628_092642.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/GLLx1DTH0VQ/uplcv?utm_term=how+to+get+avakin+coins+free
    • 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/
    • http://dejavu.sourceforge.net
    • http://dejavu.sourceforge.net/wiki/index.php/License

Extracted artifacts 3

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off0000fd25.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xFD25 16792 bytes
font_01_sfnt_off00011537.bin
21206cd2f5d35f64ec621216290708c9567c4556cb34f491294175f07143004f
pdf-font-stream PDF embedded font (sfnt) at offset 0x11537 16748 bytes
font_02_sfnt_off000140ea.bin
48ca26ae3dd3db70e764186e1d39b2074a31200c0b32b827048f1411e310f150
pdf-font-stream PDF embedded font (sfnt) at offset 0x140EA 10700 bytes