Malicious PDF — malware analysis report

Static analysis result for SHA-256 cd943352f519fe6d…

MALICIOUS

PDF

85.8 KB Created: 2021-07-04 23:56:41 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: f08737ae9af419776c3d1df3e6a4dfac SHA-1: 25884a8be52b2a5a1754e86919614829a88a31dd SHA-256: cd943352f519fe6dbc7a31ef0786547d129dbef1c4316a985d8b80820a8b9654
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1204.002 Malicious Link

The PDF contains a large number of links, many pointing to compromised WordPress sites, indicating a link farm designed to distribute malicious content or phish users. The ML classifier and ClamAV detection strongly support its malicious nature. No scripts were extracted, and the document body was unreadable, but the URL structure and heuristic firings are sufficient to determine the attack pattern.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9942

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • 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 http://www.sensible-seeds-premium.com/wp-content/plugins/formcraft/file-upload/server/content/files/16083a840ee610---93783098051.pdf
    • https://yournew.site/wp-content/plugins/super-forms/uploads/php/files/0745jg4en46e1i9l73tf7ktucj/ridebonalon.pdf
    • http://allasclub.com/campannas/file/zegemalogotujukobokife.pdf
    • http://nensi.si/upload/file/11928958596.pdf
    • http://www.elsecretodelolivo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160ac169c46c00---66181601748.pdf
    • https://tkpmission.org/wp-content/plugins/formcraft/file-upload/server/content/files/16088362e75ea4---tofinadutimakomapirafof.pdf
    • http://www.advokat.com/app/webroot/img/fck/file/tebodipon.pdf
    • http://www.sphotobooth.com/wp-content/plugins/formcraft/file-upload/server/content/files/160771d443e24d---55374903235.pdf
    • http://interface-referencement.com/userfiles/file/16984766446.pdf
    • https://inlandautorepairmurrietaca.com/wp-content/plugins/super-forms/uploads/php/files/891172cffba6dd97749b3c4746c3af79/tavevu.pdf
    • https://camile.vn/wp-content/plugins/super-forms/uploads/php/files/90507q1kjkplphkl9uqeuedk2k/55041137996.pdf
    • https://hfdjet.com/wp-content/plugins/super-forms/uploads/php/files/fe80be2481cadec988ac59c88bbcd0cc/lasak.pdf
    • http://bridgesonthepark.com/wp-content/plugins/formcraft/file-upload/server/content/files/160826686363ce---58321837772.pdf
    • http://uss100.com/clients/5/56/562308f4da1da23328cfd9e5c9f3e68f/File/7747221428.pdf
    • https://stijsr.com/userfiles/file/12770176415.pdf
    • http://everest-c.ru/ckfinder/userfiles/files/danexeti.pdf
    • http://bigandtallking.com/userfiles/file/puzoratexutakogego.pdf
    • http://blpest.com/UserFiles/file/80905601857.pdf
    • https://www.tangelo.no/wp-content/plugins/formcraft/file-upload/server/content/files/1607beb2b1e989---zosexemavelurunuvogovirig.pdf
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/acf377ae207fa6c03d559e2a037df06c/xakixene.pdf
    • https://mayxaydungthienlong.com/uploads/files/files/56243522493.pdf
    • https://readxyz.com/wp-content/plugins/super-forms/uploads/php/files/1c22402846e7e92765658a719a6bf575/50665368370.pdf
    • https://leicht-spb.ru/wp-content/plugins/super-forms/uploads/php/files/a1fb15b532f24b16c6b9b04ada1e8105/rusukajidagatimimapulevef.pdf
    • http://www.urbanwaterways.info/files/puwoxofurigibe.pdf
    • http://www.sunarozlem.com.tr/wp-content/plugins/super-forms/uploads/php/files/k7d5us09c6n2crqutiu22ro8q0/19835578802.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/BvfzZFkJO3s/uplcv?utm_term=left+lateral+wall+placenta
    • 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_off0000ecc9.bin
30099022c5e351213fce2aa618162838ce1dd03568d2be82b7b413140de5f2bf
pdf-font-stream PDF embedded font (sfnt) at offset 0xECC9 17204 bytes
font_01_sfnt_off00011987.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x11987 16792 bytes
font_02_sfnt_off0001319e.bin
be227e5c771a3ad0eb4e7280f99b4010c8f0f449e6cc65954415c83bd8d71d42
pdf-font-stream PDF embedded font (sfnt) at offset 0x1319E 10136 bytes