Malicious PDF — malware analysis report

Static analysis result for SHA-256 4b3f4fd0ee9f5936…

MALICIOUS

PDF

91.2 KB Created: 2021-06-28 05:52:01 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 5.11.3)
MD5: 681f2a919519ef543b04e4c25a92cf64 SHA-1: 4b50d3c60f6ed98e21b37248cca1251b4000e490 SHA-256: 4b3f4fd0ee9f5936b30e8458b1aa79bf33d515b9687e964e58e3591441c3ce7b
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was identified as malicious by ML classifiers and ClamAV, indicating a phishing or trojan threat. It functions as a link farm, with numerous embedded URLs pointing to compromised WordPress upload directories, likely serving as a distribution point for further malicious content. The presence of external URI heuristics and the compromised CMS upload link farm rule strongly suggest an attempt to lure users to malicious sites.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9947

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.farparts.cl/wp-content/plugins/formcraft/file-upload/server/content/files/1607c333e00cbb---pumuwetixobomukelaroz.pdf
    • http://chandigarhdatarecovery.com/files/file/temikonapoxibivupudokawo.pdf
    • http://www.combatsim.eu/wp-content/plugins/formcraft/file-upload/server/content/files/1609e3a9997f65---17433658938.pdf
    • http://hornets88.com/clients/56662/File/6167037209.pdf
    • https://stellabakingcompany.com/wp-content/plugins/formcraft/file-upload/server/content/files/16072af38ecf7b---5694074342.pdf
    • https://xn--i1aam8cb.xn--p1ai/wp-content/plugins/super-forms/uploads/php/files/21e00f6613e77c7c807fcfa2a3780c3e/23269425443.pdf
    • http://www.1000ena.com/wp-content/plugins/formcraft/file-upload/server/content/files/1607714879f59c---39108988481.pdf
    • http://trendstyleimage.com/uploads/ckfinder/userfiles/files/36745302129.pdf
    • http://gsoam.ge/wp-content/plugins/formcraft/file-upload/server/content/files/160b5940e4c3cf---dulovatinazoniwap.pdf
    • https://lastcallslc.com/wp-content/plugins/super-forms/uploads/php/files/d1010c1375076809a82258b6df810ef6/59313753813.pdf
    • http://carszana.com/image/upload/File/72919431949.pdf
    • http://johnmarzillier.com/ckfinder/userfiles/files/51809549176.pdf
    • https://accesoriosalmayor.com/images/userfiles/file/tazitozunazozirinelev.pdf
    • https://husvagnsexpo.se/wp-content/plugins/formcraft/file-upload/server/content/files/1606eee10c1110---48380247090.pdf
    • http://myconnect-thailand.com/image/upload/File/67270753661.pdf
    • http://fortlauderdalelimorental.net/wp-content/plugins/formcraft/file-upload/server/content/files/1608f44267024c---tomexakogorepunaza.pdf
    • https://www.anandtirth.com/wp-content/plugins/super-forms/uploads/php/files/df5otd6kcvokanmpo1cpu2sfn4/33389951853.pdf
    • http://plncse.hu/php_data/file/temofadif.pdf
    • http://global-poseg.com/wp-content/plugins/formcraft/file-upload/server/content/files/160abfbab23e87---56387418116.pdf
    • http://xaydungphongphu.com/uploads/files/zavuxorusedikiw.pdf
    • http://go-trec.com/wp-content/plugins/super-forms/uploads/php/files/vapi3p2g2u42986d5rolvkf7fl/56648388196.pdf
    • https://n95america.com/wp-content/plugins/super-forms/uploads/php/files/566c6f6877b474820e0c0fc7536f96c9/94881679000.pdf
    • https://janeunchained.com/wp-content/plugins/super-forms/uploads/php/files/3mil4h6inftlg5oaje8clp9lsq/rokakigiverutamibimim.pdf
    • https://funkydrop.shop/wp-content/plugins/super-forms/uploads/php/files/4b464bb45147f8e65e0dbe46ca3ddd00/gasoritikogemozuzigepije.pdf
    • https://feedproxy.google.com/~r/1eyvgo/aqOO/~3/1KS0DP0cxss/uplcv?utm_term=happy+birthday+to+my+little+brother+letter
    • 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_off00010322.bin
9d2294e344127da9ddc2b77d68b1576b6b78373885bc9da2859f180a98f2c1e1
pdf-font-stream PDF embedded font (sfnt) at offset 0x10322 16792 bytes
font_01_sfnt_off00011b34.bin
4f156c323e1b49e540d12454c2f80e52c8fdb016b59f1ca7569addf70b258a2e
pdf-font-stream PDF embedded font (sfnt) at offset 0x11B34 16348 bytes
font_02_sfnt_off00014575.bin
fea760e85882d9c99d82e1890a5160bed745f649a5b0a1dbdc340ae3ecc26ea6
pdf-font-stream PDF embedded font (sfnt) at offset 0x14575 10632 bytes