Malicious PDF — malware analysis report

Static analysis result for SHA-256 651cc2d46c60b4f8…

MALICIOUS

PDF

85.7 KB Created: 2021-07-02 23:42:50 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: c9fd5fe4fe1b484b9a6ec44f7792c4eb SHA-1: bebe04a15cc80e6c36d0810246b66188b21a6495 SHA-256: 651cc2d46c60b4f8156c53b73aafe4ce57fea2043b74f5b2c353125f8ef23acb
164 Risk Score

Malware Insights

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

This PDF file was detected as malicious by ClamAV and an ML classifier, indicating a high likelihood of malicious intent. The presence of multiple links pointing to compromised CMS upload storage and disposable hosting suggests a phishing or malware distribution scheme. Although no scripts were explicitly extracted, the file's structure and heuristic firings point towards it being used to trick users into downloading malicious content, likely via a call-to-action button.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9860

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
  • 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.
  • Visual download / call-to-action button lure low SE_DOWNLOAD_BUTTON
    Document contains a call-to-action phrase ('Click here to download', 'Download Now', etc.) — low-signal unless other findings point to a malicious workflow
  • 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://writtenmail.com/upload_images/file/71825110685.pdf
    • https://donnasalon.ru/wp-content/plugins/super-forms/uploads/php/files/b80b1e90348cfad789bcae8c327b15e0/23228480090.pdf
    • http://www.bewegeninarnhem.nl/wp-content/plugins/formcraft/file-upload/server/content/files/160b77be859b03---36049089899.pdf
    • http://aivieksteslaivas.lv/userfiles/file/62320858326.pdf
    • https://nhaban24h.com.vn/wp-content/plugins/super-forms/uploads/php/files/ue31pvcpdq4hqsv79bonbl0qe2/28456983529.pdf
    • http://aggengr.com/uploads/CMS/file/39708949104.pdf
    • http://rufullthrottle.com/wp-content/plugins/formcraft/file-upload/server/content/files/160929ddb7427c---pifixagapegita.pdf
    • http://tutek.eu/userfiles/file/20010416421.pdf
    • http://misosmile.com/upload/editor/files/12709861840.pdf
    • https://baptistfriends.org/media/95042352039.pdf
    • https://www.zulilighting.com/wp-content/plugins/super-forms/uploads/php/files/aabfe9d83f53df4c97f273d7dc36f383/vunep.pdf
    • https://ateneoarbonaida.com/wp-content/plugins/formcraft/file-upload/server/content/files/16097e7320c319---pesonurenugipusavota.pdf
    • https://makeswebsites.com/clients/c/c8/c8c605999f3d8352d7bb792cf3fdb25b/File/94538150839.pdf
    • http://www.skup.it/wp-content/plugins/formcraft/file-upload/server/content/files/160ba471a2f6e2---kokibexulebigida.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/bd70136bbf2d9e904fb4c80918a2a7b4/pasaxisapegalap.pdf
    • https://soalmatematik.com/userfiles/file/jolenutokekuwutamuwapajaw.pdf
    • http://immobilieninvestors.eu/userfiles/file/zefuserajatoripubalodim.pdf
    • http://extintoresorigen.com/images/editor/44082371729.pdf
    • http://ambvetsanprospero.eu/userfiles/files/fadufuwitu.pdf
    • http://lotuscourtpune.com/wp-content/plugins/super-forms/uploads/php/files/292rfr2jvgrh1dv46hte56adm7/sunizubituvarewuv.pdf
    • https://xn--64-mlcufjjaii0l.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/262d269de2024b4bef431ae244c4bc9a/lorebafusejizawonoxa.pdf
    • https://joefairless.com/wp-content/plugins/super-forms/uploads/php/files/e1c31c5e7289650ef859a5b42d322966/rafafelodanipe.pdf
    • https://kes-stv.ru/wp-content/plugins/super-forms/uploads/php/files/72769ecb0f99a83faf5c5834cc4242d0/99169591646.pdf
    • https://www.ezhealthcheck.com/wp-content/plugins/super-forms/uploads/php/files/iev2mbbma11iqli7u63tv6sjnq/36766613481.pdf
    • https://insights3.com/wp-content/plugins/super-forms/uploads/php/files/3936a5555c976789b26d987a7fb49569/70431526892.pdf
    • http://dabaizhongxue.com/upload_fck/file/2021-5-22/20210522220705838275.pdf
    • https://feedproxy.google.com/~r/skout/mBVl/~3/6naE_Nh8_CY/uplcv?utm_term=asimov%27s+new+guide+to+science+1993+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/
    • 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_off0000eaca.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0xEACA 16792 bytes
font_01_sfnt_off000102e1.bin
68dc09ecc06389ef1d9e49378cba6934b5680dd0bb06eae0961592f612a0a6a5
pdf-font-stream PDF embedded font (sfnt) at offset 0x102E1 11316 bytes
font_02_sfnt_off00011d86.bin
42213d09fd417497bce95e85a30ab36d1f3ebb289545687e66aa8221eb157d66
pdf-font-stream PDF embedded font (sfnt) at offset 0x11D86 16796 bytes