Malicious PDF — malware analysis report

Static analysis result for SHA-256 66abf2ed586c5736…

MALICIOUS

PDF

86.3 KB Created: 2021-07-09 20:27:49 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 686734779fdcdabd146de31366b722f8 SHA-1: 8f42986d62b2b6c0a1301e107110dd73cb5b4f9a SHA-256: 66abf2ed586c5736690246c6bbf2cc0cc34f76ff20edcd786eb6797708e861bd
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment T1059.007 JavaScript

The PDF contains numerous embedded URLs, many of which point to compromised CMS uploads and are structured as a link farm. The ML classifier and ClamAV detection strongly indicate malicious intent, likely phishing or malware delivery. While no scripts were explicitly extracted, the PDF structure and URL patterns are consistent with attempts to lure users to external sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9952

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2528dad23a95d95-d2528dad23a95d95-10044376-0
  • 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 https://coretry.ru/uplcv?utm_term=current+research+in+mathematics+education+pdf
    • http://www.miamiairportlimo.net/wp-content/plugins/formcraft/file-upload/server/content/files/160a8046edd73a---fepedijimuxudivabas.pdf
    • https://study-go.info/wp-content/plugins/super-forms/uploads/php/files/03882fd4f0f6925ebf83a5e3ebbc7c37/pogogobegoradebijijatub.pdf
    • https://www.sanier.pl/wp-content/plugins/super-forms/uploads/php/files/4s8dtpjlsocbk8qref4lp2gno0/zafoxotokul.pdf
    • http://www.icodar.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a6e6b0ed6c---2531842492.pdf
    • https://www.picmephotoboothhire.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/160810e3316c00---72712885966.pdf
    • http://themultifold.com/wp-content/plugins/super-forms/uploads/php/files/u99rsi4jn9ns1rihqqphgvpqt6/pubivorokizoronokuwaxemor.pdf
    • https://www.darrellstuckey.com/wp-content/plugins/formcraft/file-upload/server/content/files/16094497960753---64751921907.pdf
    • http://kaplanpm.com/wp-content/plugins/formcraft/file-upload/server/content/files/1606fc0d6a506a---xowijaji.pdf
    • https://www.straightmyteeth.com/wp-content/plugins/super-forms/uploads/php/files/ba5541b9b5d67213d82eb337b332c989/49296841265.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/gbunm1gi4edecvrn28s5aanmkg/18590348593.pdf
    • https://vizzzio.ru/wp-content/plugins/super-forms/uploads/php/files/9b855c66c420fa67a7dc95cf6af6dd37/bozekoweti.pdf
    • https://harpethvalleypto.org/wp-content/plugins/super-forms/uploads/php/files/f535211e5988e80343970b3cd74dceb8/dorisopem.pdf
    • http://mtjjt.com/2013/upload/article/files/210624112126924910szkei.pdf
    • http://www.maoles.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a9221483a0c---58289891688.pdf
    • http://www.gametimecatering.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608169905a40a---famekesidetifukevof.pdf
    • http://joshuadacosta.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b280363ba80---wojepasujovivirabubavisa.pdf
    • http://www.phonefixcomo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5507131f81---85235852635.pdf
    • https://www.sharpeningfactory.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b149e1a2f71---83411774140.pdf
    • https://www.capitalroofingct.com/wp-content/plugins/formcraft/file-upload/server/content/files/1608e610612d27---lusaju.pdf
    • https://michaels-limo.com/wp-content/plugins/formcraft/file-upload/server/content/files/160b5f386f41a2---78176247879.pdf
    • https://www.sussexweddingservices.co.uk/wp-content/plugins/formcraft/file-upload/server/content/files/16095e0a417f53---foxegekawulosujonanavejo.pdf
    • https://sckprime.com/wp-content/plugins/super-forms/uploads/php/files/0859daa1068278f0d60925f11e8f4b30/xobanejufasevode.pdf
    • https://alakharia.com/public_html/userfiles/file/mapimururoxemopun.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_off0000ef11.bin
570d822df7e2e5f74d54106cbe38a300da13760581b7fd6c9747b0668a775f3f
pdf-font-stream PDF embedded font (sfnt) at offset 0xEF11 10972 bytes
font_01_sfnt_off0001085d.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x1085D 16792 bytes
font_02_sfnt_off0001206f.bin
1cac444e1997d11dc326f3c35e9f56fc2c447f718eba9f9a7d2f1858e701a32f
pdf-font-stream PDF embedded font (sfnt) at offset 0x1206F 16884 bytes