Malicious PDF — malware analysis report

Static analysis result for SHA-256 a8ef582ae81397e1…

MALICIOUS

PDF

86.1 KB Created: 2021-06-26 22:38:18 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 51bed4f13f168a3f464ab8924cc9cdff SHA-1: 8c20da2347ef46b022b0a7aabb2225b8d66ce2e6 SHA-256: a8ef582ae81397e1cd9dd38a4b0eac66d635f61d6b9749491d5d6c7c8fc99cfb
176 Risk Score

Malware Insights

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

The file is identified as malicious by ML classifiers and ClamAV, with high-confidence heuristics indicating it's a phishing or malware distribution lure. It contains multiple links to compromised WordPress upload storage and disposable hosting, suggesting an attempt to redirect users to malicious content. The PDF structure and embedded URIs point towards an exploitation attempt, likely for initial access via spearphishing.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9964

Heuristics 7

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • Clickable URI points to raw IP address medium PDF_URI_IP_LITERAL
    PDF contains a clickable HTTP(S) action whose host is a literal IPv4 address. Legitimate documents normally link to named domains; raw-IP destinations are common in disposable phishing and malware-delivery infrastructure.
  • 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://chmelo.hu/sites/default/files/file/xegesutadozugivafoligoz.pdf
    • http://www.immiflex.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b552ec19bd0---66051413424.pdf
    • http://hrdiborice.cz/erucom1/files/files/zixiv.pdf
    • http://sungsam.net/userData/board/file/49909301872.pdf
    • https://velvetskin.pl/wp-content/plugins/super-forms/uploads/php/files/e5512bb1d6041f37cdf70bb2bbb9c324/34028057812.pdf
    • http://104.156.58.56/~web2inbox/wp-content/plugins/formcraft/file-upload/server/content/files/160c3d03c2bc05---romejeworibukamo.pdf
    • https://actorconseil.com/files/file/zupanovobuzabomipafosim.pdf
    • http://countrysquirefoods.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606e8fa6bc637---43969356516.pdf
    • https://cornwallstaffagency.com/userfiles/file/kunojikatasiko.pdf
    • http://baohanhranghm.com/upload/img/files/38961024222.pdf
    • https://nicemexico.net/wp-content/plugins/formcraft/file-upload/server/content/files/160ab880b1e463---revikizamubip.pdf
    • http://counterreaction.net/wp-content/plugins/formcraft/file-upload/server/content/files/160af938e8c999---romizobes.pdf
    • http://www.virtualaid.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1606c825501fb9---ketudasizoporizuwigisilex.pdf
    • http://premiumresourcing.com/wp-content/plugins/formcraft/file-upload/server/content/files/160776246af003---mozurumogored.pdf
    • http://afghansolar.com/userfiles/file/69096351778.pdf
    • http://josephfellerlaw.com/customer/3/d/9/3d947ad6ce2568d98b832ccf5548371bFile/vasawabujijus.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607a070874422---83242363779.pdf
    • http://www.k-24.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609e9301a4de3---rojirorufiwexifode.pdf
    • http://www.emailposte.com/pictures/91208593871.pdf
    • https://www.phoenixdentalacademy.co.uk/wp-content/plugins/super-forms/uploads/php/files/b97f1872883660a309a8524dc48edd63/tikejolelokepovijara.pdf
    • https://diversifiedhumansolutions.com/wp-content/plugins/super-forms/uploads/php/files/1c739de5765ff60fab8965202128b30a/48549382809.pdf
    • https://pasarantogel2.com/contents//files/radozitowobogituwikaxinoz.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=present+continuous+text+comprehension
    • 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_off0000e9ca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xE9CA 16792 bytes
font_01_sfnt_off000101e1.bin
a7041bc589f43000ea9022b523e5f638db8bb4b7f517d6bded5dfa71eb7e2fde
pdf-font-stream PDF embedded font (sfnt) at offset 0x101E1 10636 bytes
font_02_sfnt_off00011a0f.bin
55416bbc0e4b38cbc591abf41c5b0fda1b0afe5c93d78dbf746c901f23d2de59
pdf-font-stream PDF embedded font (sfnt) at offset 0x11A0F 18868 bytes